Utilities
-------------

.. _ChecksumAddress: https://eth-typing.readthedocs.io/en/latest/types.html#checksumaddress
.. _HexAddress: https://eth-typing.readthedocs.io/en/latest/types.html#hexaddress
.. _Address: https://eth-typing.readthedocs.io/en/latest/types.html#address
.. _HexStr: https://eth-typing.readthedocs.io/en/latest/types.html#hexstr

All functions can be imported directly from the ``eth_utils`` module

Alternatively, you can get the curried version of the functions by
importing them through the ``curried`` module like so:

.. doctest::

    >>> from eth_utils.curried import hexstr_if_str

ABI Utilities
~~~~~~~~~~~~~

The Application Binary Interface (ABI) may be used for encoding or decoding
transactional data. Components of an ABI may include a descriptor of each Function or
Event in the contract. The following utilities provide convenient methods for parsing
components of an ABI and encoding function parameters for use in transactions.

For more information about the ABI spec, see the Solidity
`Contract ABI specification <https://docs.soliditylang.org/en/v0.8.25/abi-spec.html>`_.

.. automodule:: eth_utils.abi
   :members:
   :undoc-members:
   :show-inheritance:

Applicators
~~~~~~~~~~~

Applicators help you apply “formatters” in various ways, most notably:

-  apply formatters to values by key
-  apply formatters to lists by index
-  conditionally applying a formatter
-  conditionally applying one of several formatters.

Here we define a “formatter” as any ``callable`` that may be called with
a single positional argument. It returns the “formatted” result. For
example ``int()`` could be used as a formatter.

Defining your own formatter is easy:

.. code:: py

    def i_put_my_thing_down_flip_it_and_reverse_it(lyric):
        return ''.join(reversed(lyric))

These tools often work nicely when curried. Import them from the
``curried`` module to get that capability built in, like
``from eth_utils.curried import apply_formatter_if``.

``apply_formatter_if(condition, formatter, value)`` -> new_value
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function will apply the formatter only if
``bool(condition()) is True``.

.. doctest::

    >>> from eth_utils.curried import apply_formatter_if, is_string

    >>> bool_if_string = apply_formatter_if(is_string, bool)

    >>> bool_if_string(1)
    1
    >>> bool_if_string('1')
    True
    >>> bool_if_string('')
    False

``apply_one_of_formatters(condition_formatter_pairs, value)`` -> new_value
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function will iterate through ``condition_formatter_pairs``, and
apply the first formatter which has a truthy condition. One of the
formatters *must* match, or this function will raise a ``ValueError``.

.. code:: py

    >>> from eth_utils.curried import apply_one_of_formatters, is_string, is_list_like

    >>> multi_formatter = apply_one_of_formatters((
        (is_list_like, tuple),
        (is_string, i_put_my_thing_down_flip_it_and_reverse_it),
    )
    >>> multi_formatter('my thing')
    'gniht ym'
    >>> multi_formatter([1, 2])
    (1, 2)
    >>> multi_formatter(54)
    ValueError("The provided value did not satisfy any of the formatter conditions")

``apply_formatter_at_index(formatter, at_index, <list_like>)`` -> <new_list_like>
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function will apply the formatter to one element of ``list_like``,
at position ``at_index``, and return a new iterable with that element
replaced. The returned value will be the same type as the one passed
into the third argument.

.. doctest::

    >>> from eth_utils.curried import apply_formatter_at_index

    >>> targetted_formatter = apply_formatter_at_index(bool, 1)

    >>> targetted_formatter((1, 2, 3))
    (1, True, 3)

    >>> targetted_formatter([1, 2, 3])
    [1, True, 3]

``apply_formatter_to_array(formatter, <list_like>)`` -> <new_list_like>
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function will apply the formatter to each element of ``list_like``.
It returns the same type as the ``list_like`` argument

.. doctest::

    >>> from eth_utils.curried import apply_formatter_to_array

    >>> map_int = apply_formatter_to_array(int)

    >>> map_int((1.2, 3.4, 5.6))
    (1, 3, 5)

    >>> map_int([1.2, 3.4, 5.6])
    [1, 3, 5]

``apply_formatters_to_sequence(formatters, <list_like>)`` -> <new_list_like>
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function will apply each formatter at to the list-like value, at
the position it was supplied. It returns the same time as the
``list_like`` argument. For example:

.. doctest::

    >>> from eth_utils.curried import apply_formatters_to_sequence

    >>> list_formatter = apply_formatters_to_sequence([bool, int, str])

    >>> list_formatter([1.2, 3.4, 5.6])
    [True, 3, '5.6']

    >>> list_formatter((1.2, 3.4, 5.6))
    (True, 3, '5.6')

    # Formatters and list-like value must be the same length

    >>> list_formatter((1.2, 3.4, 5.6, 7.8))
    Traceback (most recent call last):
    IndexError: Too few formatters for sequence: 3 formatters for (1.2, 3.4, 5.6, 7.8)

    >>> list_formatter((1.2, 3.4))
    Traceback (most recent call last):
    IndexError: Too many formatters for sequence: 3 formatters for (1.2, 3.4)

``combine_argument_formatters(*formatters)`` -> lambda <list_like>: <new_list_like>
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**DEPRECATED**

You can replace all current versions of:

.. doctest::

    >>> from eth_utils import combine_argument_formatters

    >>> list_formatter = combine_argument_formatters(bool, int, str)

With the newer, preferred:

.. doctest::

    >>> from eth_utils.curried import apply_formatters_to_sequence

    >>> list_formatter = apply_formatters_to_sequence((bool, int, str))

The old usage works like:

Combine several formatters to be applied to a list-like value, each
formatter at the position it was supplied. The new formatter will return
the same type as it was supplied. For example:

.. doctest::

    >>> from eth_utils import combine_argument_formatters

    >>> list_formatter = combine_argument_formatters(bool, int, str)

    >>> list_formatter([1.2, 3.4, 5.6])
    [True, 3, '5.6']

    >>> list_formatter((1.2, 3.4, 5.6))
    (True, 3, '5.6')

    # it will pass through items longer than the number of formatters supplied
    >>> list_formatter((1.2, 3.4, 5.6, 7.8))
    (True, 3, '5.6', 7.8)

``apply_formatters_to_dict(formatter_dict, <dict_like>, unaliased=False)`` -> dict
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function will apply the formatter to the element with the matching
key in ``dict_like``, passing through values with keys that have no
matching formatter.

.. doctest::

    >>> from eth_utils.curried import apply_formatters_to_dict

    >>> dict_formatter = apply_formatters_to_dict({
    ...    'should_be_int': int,
    ...    'should_be_bool': bool,
    ... })

    >>> result = dict_formatter({
    ...    'should_be_int': 1.2,
    ...    'should_be_bool': 3.4,
    ...    'pass_through': 5.6,
    ... })
    >>> result == {'should_be_int': 1, 'should_be_bool': True, 'pass_through': 5.6}
    True

The ``CamelModel`` pydantic model is included in expected dict-like types. If the
dict-like object is an instance of a ``CamelModel``, the ``unaliased`` argument
can be set to ``True`` to pre-serialize the object as "non-aliased", according to
pydantic. By default, it will be pre-serialized as "aliased", which ``CamelModel``
interprets as camelCase keys.

.. doctest::

    >>> from eth_utils.curried import apply_formatters_to_dict
    >>> from eth_utils import CamelModel, to_bytes, to_int
    >>> from pydantic import Field

    >>> class PydanticModel(CamelModel):
    ...     to_bytes_from_int: int = 1
    ...     to_int_from_bytes: bytes = b"\x02"
    ...     # class fields excluded from serialization
    ...     excluded_field: int = Field(default=3, exclude=True)
    ...     excluded_field_two: str = Field(default="4", exclude=True)

    >>> dict_formatter = apply_formatters_to_dict({
    ...     "toBytesFromInt": to_bytes,
    ...     "toIntFromBytes": to_int
    ... })

    >>> dict_formatter(PydanticModel())
    {'toBytesFromInt': b'\x01', 'toIntFromBytes': 2}


``apply_key_map(formatter_dict, <dict_like>)`` -> dict
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function will rename keys from using the lookups provided in
``formatter_dict``. It will pass through any unspecified keys.

.. doctest::

    >>> from eth_utils.curried import apply_key_map

    >>> dict_key_map = apply_key_map({
    ...    'black': 'orange',
    ...    'Internet': 'Ethereum',
    ... })

    >>> result = dict_key_map({
    ...    'black': 1.2,
    ...    'Internet': 3.4,
    ...    'pass_through': 5.6,
    ... })
    >>> result == {'orange': 1.2, 'Ethereum': 3.4, 'pass_through': 5.6}
    True

Address Utils
~~~~~~~~~~~~~

``is_address(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if the ``value`` is one of the following accepted
address formats.

-  20 byte hexadecimal, upper/lower/mixed case, with or without ``0x``
    prefix:

    -  ``'d3cda913deb6f67967b99d67acdfa1712c293601'``
    -  ``'0xd3cda913deb6f67967b99d67acdfa1712c293601'``
    -  ``'0xD3CDA913DEB6F67967B99D67ACDFA1712C293601'``
    -  ``'0xd3CdA913deB6f67967B99D67aCDFa1712C293601'``

-  20 byte hexadecimal padded to 32 bytes with null bytes,
    upper/lower/mixed case, with or without ``0x`` prefix:

    -  ``'000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601'``
    -  ``'000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601'``
    -  ``'0x000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601'``
    -  ``'0x000000000000000000000000D3CDA913DEB6F67967B99D67ACDFA1712C293601'``
    -  ``'0x000000000000000000000000d3CdA913deB6f67967B99D67aCDFa1712C293601'``

-  20 text or bytes string:

    -  ``'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01'``

This function has two special cases when it will return False:

-  a 20-byte hex string that has mixed case, with an invalid checksum
-  a 32-byte value that is all null bytes

.. doctest::

    >>> from eth_utils import is_address
    >>> is_address('d3cda913deb6f67967b99d67acdfa1712c293601')
    True
    >>> is_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    True
    >>> is_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    True
    >>> is_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    True
    >>> is_address('000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_address('000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_address('0x000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_address('0x000000000000000000000000D3CDA913DEB6F67967B99D67ACDFA1712C293601')
    False
    >>> is_address('0x000000000000000000000000d3CdA913deB6f67967B99D67aCDFa1712C293601')
    False
    >>> is_address(b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    True
    >>> is_address('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    False
    >>> is_address('0x0000000000000000000000000000000000000000000000000000000000000000')
    False
    >>> is_address('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
    False

``is_hex_address(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Return ``True`` if the value is a 20 byte hexadecimal encoded string in
any of upper/lower/mixed casing, with or without the ``0x`` prefix.
Otherwise return ``False``

-  ``'d3cda913deb6f67967b99d67acdfa1712c293601'``
-  ``'0xd3cda913deb6f67967b99d67acdfa1712c293601'``
-  ``'0xD3CDA913DEB6F67967B99D67ACDFA1712C293601'``
-  ``'0xd3CdA913deB6f67967B99D67aCDFa1712C293601'``

.. doctest::

    >>> from eth_utils import is_hex_address
    >>> is_hex_address('d3cda913deb6f67967b99d67acdfa1712c293601')
    True
    >>> is_hex_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    True
    >>> is_hex_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    True
    >>> is_hex_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    True
    >>> is_hex_address('000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_hex_address('000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_hex_address('0x000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_hex_address('0x000000000000000000000000D3CDA913DEB6F67967B99D67ACDFA1712C293601')
    False
    >>> is_hex_address('0x000000000000000000000000d3CdA913deB6f67967B99D67aCDFa1712C293601')
    False
    >>> is_hex_address('\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    False
    >>> is_hex_address('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    False
    >>> is_hex_address('0x0000000000000000000000000000000000000000000000000000000000000000')
    False
    >>> is_hex_address('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
    False

``is_binary_address(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Return ``True`` if the value is a 20 byte string.

.. doctest::

    >>> from eth_utils import is_binary_address
    >>> is_binary_address('d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_binary_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_binary_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    False
    >>> is_binary_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    False
    >>> is_binary_address('000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_binary_address('000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_binary_address('0x000000000000000000000000d3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_binary_address('0x000000000000000000000000D3CDA913DEB6F67967B99D67ACDFA1712C293601')
    False
    >>> is_binary_address('0x000000000000000000000000d3CdA913deB6f67967B99D67aCDFa1712C293601')
    False
    >>> is_binary_address(b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    True
    >>> is_binary_address('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    False
    >>> is_binary_address('0x0000000000000000000000000000000000000000000000000000000000000000')
    False
    >>> is_binary_address('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
    False

``is_canonical_address(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if the ``value`` is an address in its canonical form.

The canonical representation of an address according to ``eth_utils`` is
a 20 byte long string of bytes, eg:
``b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01'``

.. doctest::

    >>> from eth_utils import is_canonical_address
    >>> is_canonical_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_canonical_address(b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    True
    >>> is_canonical_address('\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01xd')
    False

``is_checksum_address(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if the ``value`` is a checksummed address as specified
by `ERC55 <https://github.com/ethereum/EIPs/issues/55>`__

.. doctest::

    >>> from eth_utils import is_checksum_address
    >>> is_checksum_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    True
    >>> is_checksum_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_checksum_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    False
    >>> is_checksum_address('0x52908400098527886E0F7030069857D2E4169EE7')
    True
    >>> is_checksum_address('0xde709f2102306220921060314715629080e2fb77')
    True

``is_checksum_formatted_address(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if the ``value`` is formatted as an
`ERC55 <https://github.com/ethereum/EIPs/issues/55>`__ checksum address.

.. doctest::

    >>> from eth_utils import is_checksum_formatted_address
    >>> is_checksum_formatted_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    True
    >>> is_checksum_formatted_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    False
    >>> is_checksum_formatted_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    False
    >>> is_checksum_formatted_address('0x52908400098527886E0F7030069857D2E4169EE7')
    False
    >>> is_checksum_formatted_address('0xde709f2102306220921060314715629080e2fb77')
    False

``is_normalized_address(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if the ``value`` is an address in its normalized form.

The normalized representation of an address is the lowercased 20 byte
hexadecimal format.

.. doctest::

    >>> from eth_utils import is_normalized_address
    >>> is_normalized_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    False
    >>> is_normalized_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    True
    >>> is_normalized_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    False
    >>> is_normalized_address('0x52908400098527886E0F7030069857D2E4169EE7')
    False
    >>> is_normalized_address('0xde709f2102306220921060314715629080e2fb77')
    True

``is_same_address(a, b)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if both ``a`` and ``b`` are valid addresses according
to the ``is_address`` function and that they are both representations of
the same address.

.. doctest::

    >>> from eth_utils import is_same_address
    >>> is_same_address('0xd3cda913deb6f67967b99d67acdfa1712c293601', '0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    True
    >>> is_same_address('0xd3cda913deb6f67967b99d67acdfa1712c293601', '0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    True
    >>> is_same_address('0xd3cda913deb6f67967b99d67acdfa1712c293601', b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    True


``to_canonical_address(value)`` -> Address_
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Given any valid representation of an address return its canonical form.

.. doctest::

    >>> from eth_utils import to_canonical_address
    >>> to_canonical_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01'
    >>> to_canonical_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01'
    >>> to_canonical_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01'
    >>> to_canonical_address(b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01'

``to_checksum_address(value)`` -> ChecksumAddress_
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Given any valid representation of an address return the checksummed
representation.

.. doctest::

    >>> from eth_utils import to_checksum_address
    >>> to_checksum_address('0xd3cda913deb6f67967b99d67acdfa1712c293601')
    '0xd3CdA913deB6f67967B99D67aCDFa1712C293601'
    >>> to_checksum_address('0xD3CDA913DEB6F67967B99D67ACDFA1712C293601')
    '0xd3CdA913deB6f67967B99D67aCDFa1712C293601'
    >>> to_checksum_address('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
    '0xd3CdA913deB6f67967B99D67aCDFa1712C293601'
    >>> to_checksum_address(b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')
    '0xd3CdA913deB6f67967B99D67aCDFa1712C293601'


``to_normalized_address(value)`` -> HexAddress_
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Given any valid representation of an address return the normalized
representation.

.. doctest::

    >>> from eth_utils import to_normalized_address
    >>> to_normalized_address(b'\xd3\xcd\xa9\x13\xde\xb6\xf6yg\xb9\x9dg\xac\xdf\xa1q,)6\x01')  # raw bytes
    '0xd3cda913deb6f67967b99d67acdfa1712c293601'
    >>> to_normalized_address('c6d9d2cd449a754c494264e1809c50e34d64562b')  # hex encoded
    '0xc6d9d2cd449a754c494264e1809c50e34d64562b'
    >>> to_normalized_address('0xc6d9d2cd449a754c494264e1809c50e34d64562b')  # hex encoded
    '0xc6d9d2cd449a754c494264e1809c50e34d64562b'
    >>> to_normalized_address('0XC6D9D2CD449A754C494264E1809C50E34D64562B')  # cap-cased
    '0xc6d9d2cd449a754c494264e1809c50e34d64562b'

Conversion Utils
~~~~~~~~~~~~~~~~

These methods convert values using standard practices in the Ethereum
ecosystem. For example, strings are encoded to binary using UTF-8.

Because there is no reliable way to distinguish between text and a
hex-encoded bytestring, you must explicitly specify which of the two is
being supplied when passing in a ``str``.

*Only supply one of the arguments:*

``to_bytes(<bytes/int/bool/bytearray/memoryview>, text=<str>, hexstr=<str>)`` -> bytes
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Takes a variety of inputs and returns its bytes equivalent. Text gets
encoded as UTF-8.

.. doctest::

    >>> from eth_utils import to_bytes
    >>> to_bytes(0)
    b'\x00'
    >>> to_bytes(0x000F)
    b'\x0f'
    >>> to_bytes(b'')
    b''
    >>> to_bytes(b'\x00\x0F')
    b'\x00\x0f'
    >>> to_bytes(False)
    b'\x00'
    >>> to_bytes(True)
    b'\x01'
    >>> to_bytes(hexstr='0x000F')
    b'\x00\x0f'
    >>> to_bytes(hexstr='000F')
    b'\x00\x0f'
    >>> to_bytes(text='')
    b''
    >>> to_bytes(text='cowmö')
    b'cowm\xc3\xb6'

``to_hex(<bytes/int/bool/bytearray/memoryview>, text=<str>, hexstr=<str>)`` -> HexStr_
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Takes a variety of inputs and returns it in its hexadecimal
representation. It follows the rules for converting to hex in the
JSON-RPC spec. Roughly, it leaves leading 0s on bytes input, and trims
leading zeros on int input.

.. doctest::

    >>> from eth_utils import to_hex
    >>> to_hex(0)
    '0x0'
    >>> to_hex(1)
    '0x1'
    >>> to_hex(0x0)
    '0x0'
    >>> to_hex(0x000F)
    '0xf'
    >>> to_hex(b'')
    '0x'
    >>> to_hex(b'\x00\x0F')
    '0x000f'
    >>> to_hex(False)
    '0x0'
    >>> to_hex(True)
    '0x1'
    >>> to_hex(hexstr='0x000F')
    '0x000f'
    >>> to_hex(hexstr='000F')
    '0x000f'
    >>> to_hex(text='')
    '0x'
    >>> to_hex(text='cowmö')
    '0x636f776dc3b6'

``to_int(<bytes/int/bool/bytearray/memoryview>, text=<str>, hexstr=<str>)`` -> int
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Takes a variety of inputs and returns its integer equivalent.

.. doctest::

    >>> from eth_utils import to_int
    >>> to_int(0)
    0
    >>> to_int(0x000F)
    15
    >>> to_int(b'\x00\x0F')
    15
    >>> to_int(False)
    0
    >>> to_int(True)
    1
    >>> to_int(hexstr='0x000F')
    15
    >>> to_int(hexstr='000F')
    15

``to_text(<bytes/int/bool/bytearray/memoryview>, text=<str>, hexstr=<str>)`` -> str
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Takes a variety of inputs and returns its string equivalent. Text gets
decoded as UTF-8.

.. doctest::

    >>> from eth_utils import to_text
    >>> to_text(0x636f776dc3b6)
    'cowmö'
    >>> to_text(b'cowm\xc3\xb6')
    'cowmö'
    >>> to_text(hexstr='0x636f776dc3b6')
    'cowmö'
    >>> to_text(hexstr='636f776dc3b6')
    'cowmö'
    >>> to_text(text='cowmö')
    'cowmö'

``text_if_str(to_type, text_or_primitive)`` -> T
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Convert `text_or_primitive` with the provided `to_type` function. Assumes the input string or primitive will be unicode `text`.

Return type `T` is the same as the return type of the provided `to_type` function.

.. doctest::

    >>> from eth_utils import text_if_str, to_bytes
    >>> text_if_str(to_bytes, 0)
    b'\x00'
    >>> text_if_str(to_hex, 0)
    '0x0'
    >>> text_if_str(to_int, 0)
    0
    >>> text_if_str(to_text, 0)
    '\x00'

``hexstr_if_str(to_type, text_or_primitive)`` -> T
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Convert `text_or_primitive` with the provided `to_type` function. Assumes the input string or primitive will be `hexstr`.

Return type `T` is the same as the return type of the provided `to_type` function.

.. doctest::

    >>> from eth_utils import hexstr_if_str, to_bytes
    >>> hexstr_if_str(to_bytes, '0x000F')
    b'\x00\x0f'
    >>> hexstr_if_str(to_hex, '0x000F')
    '0x000f'
    >>> hexstr_if_str(to_int, '0x000F')
    15
    >>> hexstr_if_str(to_text, '0x000F')
    '\x00\x0f'

Crypto Utils
~~~~~~~~~~~~

Because there is no reliable way to distinguish between text and a
hex-encoded bytestring, you must explicitly specify which of the two is
being supplied when passing in a ``str``.

Only supply one of the arguments:

``keccak(<bytes/int/bool>, text=<str>, hexstr=<str>)`` -> bytes
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. doctest::

    >>> from eth_utils import keccak
    >>> keccak(text='')
    b"\xc5\xd2F\x01\x86\xf7#<\x92~}\xb2\xdc\xc7\x03\xc0\xe5\x00\xb6S\xca\x82';{\xfa\xd8\x04]\x85\xa4p"

    # A series of equivalent hash inputs:

    >>> keccak(text='☢')
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

    >>> keccak(0xe298a2)
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

    >>> keccak(b'\xe2\x98\xa2')
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

    >>> keccak(hexstr='0xe298a2')
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

**Please Note** - When using Python’s native hex literals, python
converts the hex to an int, so leading 0 bytes are truncated. But all
other formats maintain zeros on the left. Hex literals are only padded
until a whole number of bytes are provided to keccak. For example:

.. doctest::

    >>> keccak(0xe298a2)
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

    >>> keccak(0x0e298a2)
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

    >>> keccak(0x00e298a2)
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

    >>> keccak(0x000e298a2)
    b'\x85\xe8\x07"\xeb\x93\r\xe9;\xcc\xa8{\xa5\xdf\xda\x89\n\xa12\x95\xae\xad.\xec\xc9\x0b\xb2\xd9z\x14\x93\x16'

    >>> keccak(hexstr='0x0e298a2')
    b'i\x0f$\xbd\xbe\xf7c\xbb\xb9M\xd9\x12H"\x9f\x1f\x87\\E\xa36\xc2\xea,\x8f.\r\xf5\x95\xdc\x19\x9b'

    >>> keccak(hexstr='0x00e298a2')
    b'i\x0f$\xbd\xbe\xf7c\xbb\xb9M\xd9\x12H"\x9f\x1f\x87\\E\xa36\xc2\xea,\x8f.\r\xf5\x95\xdc\x19\x9b'

    >>> keccak(hexstr='0x000e298a2')
    b'!$Ezy\xdeU<\xec\x1f\xd1\x10\x05\xff\x11\xfc=J\xcf\xd5H\x0f\xb3c\xcc\xb5\xae\xb1\x1eA\x8b\xd3'

Currency Utils
~~~~~~~~~~~~~~

``denoms``
^^^^^^^^^^

Object with property access to all of the various denominations for
ether. Available denominations are:

+--------------+---------------------------------+
| denomination | amount in wei                   |
+==============+=================================+
| wei          | 1                               |
+--------------+---------------------------------+
| kwei         | 1000                            |
+--------------+---------------------------------+
| babbage      | 1000                            |
+--------------+---------------------------------+
| femtoether   | 1000                            |
+--------------+---------------------------------+
| mwei         | 1000000                         |
+--------------+---------------------------------+
| lovelace     | 1000000                         |
+--------------+---------------------------------+
| picoether    | 1000000                         |
+--------------+---------------------------------+
| gwei         | 1000000000                      |
+--------------+---------------------------------+
| shannon      | 1000000000                      |
+--------------+---------------------------------+
| nanoether    | 1000000000                      |
+--------------+---------------------------------+
| nano         | 1000000000                      |
+--------------+---------------------------------+
| szabo        | 1000000000000                   |
+--------------+---------------------------------+
| microether   | 1000000000000                   |
+--------------+---------------------------------+
| micro        | 1000000000000                   |
+--------------+---------------------------------+
| finney       | 1000000000000000                |
+--------------+---------------------------------+
| milliether   | 1000000000000000                |
+--------------+---------------------------------+
| milli        | 1000000000000000                |
+--------------+---------------------------------+
| ether        | 1000000000000000000             |
+--------------+---------------------------------+
| kether       | 1000000000000000000000          |
+--------------+---------------------------------+
| grand        | 1000000000000000000000          |
+--------------+---------------------------------+
| mether       | 1000000000000000000000000       |
+--------------+---------------------------------+
| gether       | 1000000000000000000000000000    |
+--------------+---------------------------------+
| tether       | 1000000000000000000000000000000 |
+--------------+---------------------------------+

.. doctest::

    >>> from eth_utils import denoms
    >>> denoms.wei
    1
    >>> denoms.finney
    1000000000000000
    >>> denoms.ether
    1000000000000000000

``to_wei(value, denomination)`` -> integer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Converts ``value`` in the given ``denomination`` to its equivalent in
the *wei* denomination.

.. doctest::

    >>> from eth_utils import to_wei
    >>> to_wei(1, 'ether')
    1000000000000000000

``to_wei_decimals(value, decimals)`` -> integer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Converts ``value`` in the given ``denomination`` to its equivalent in
the *wei* denomination.

.. doctest::

    >>> from eth_utils import to_wei_decimals
    >>> to_wei_decimals(1, 18)
    1000000000000000000

``from_wei(value, denomination)`` -> decimal.Decimal
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Converts the ``value`` in the *wei* denomination to its equivalent in
the given ``denomination``. Return value is a ``decimal.Decimal`` with
the appropriate precision to be a lossless conversion.

.. doctest::

    >>> from eth_utils import from_wei
    >>> from_wei(1000000000000000000, 'ether')
    Decimal('1')
    >>> from_wei(123456789, 'ether')
    Decimal('1.23456789E-10')

``from_wei_decimals(value, decimals)`` -> decimal.Decimal
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Converts the ``value`` in the *wei* denomination to the number of specified
decimals. Return value is a ``decimal.Decimal`` with
the appropriate precision to be a lossless conversion.

.. doctest::

    >>> from eth_utils import from_wei_decimals
    >>> from_wei_decimals(100, 3)
    Decimal('0.1')
    >>> from_wei_decimals(123456789, 18)
    Decimal('1.23456789E-10')

Debug Utils
~~~~~~~~~~~

Generate environment info
^^^^^^^^^^^^^^^^^^^^^^^^^

At the shell:

.. code:: sh

    $ python -m eth_utils

    Python version:
    3.5.3 (default, Nov 23 2017, 11:34:05)
    [GCC 6.3.0 20170406]

    Operating System: Linux-4.10.0-42-generic-x86_64-with-Ubuntu-17.04-zesty

    pip freeze result:
    bumpversion==0.5.3
    cytoolz==0.9.0
    flake8==3.4.1
    ipython==6.2.1
    pytest==3.3.2
    virtualenv==15.1.0
    ... etc

Decorators
~~~~~~~~~~

``@combomethod``
^^^^^^^^^^^^^^^^

Decorates methods in a class that can be called as both an instance
method or a ``@classmethod``.

Use the decorator like so:

.. doctest::

    >>> from eth_utils import combomethod

    >>> class Storage:
    ...    val = 1
    ...
    ...    @combomethod
    ...    def get(combo):
    ...        if isinstance(combo, type):
    ...            print("classmethod call")
    ...        elif isinstance(combo, Storage):
    ...            print("instance method call")
    ...        else:
    ...            raise TypeError("Unreachable, unless you really monkey around")
    ...        return combo.val
    ...

As usual, instances create their own copy on assignment.

.. doctest::

    >>> store = Storage()
    >>> store.val = 2

    >>> store.get()
    instance method call
    2

    >>> Storage.get()
    classmethod call
    1

``@replace_exceptions``
^^^^^^^^^^^^^^^^^^^^^^^

Replaces `Old` exceptions in a method with `New` exceptions.
Accepts a Dict, with `Old` exceptions pointing to
`New` exceptions.

.. doctest::

    >>> from eth_utils import replace_exceptions

    >>> @replace_exceptions({TypeError: AttributeError})
    ... def thing(self):
    ...     if True:
    ...         raise TypeError

    >>> thing()
    Traceback (most recent call last):
       ...
    AttributeError

Calling `thing()` will raise an `AttributeError`

Encoding Utils
~~~~~~~~~~~~~~

``big_endian_to_int(value)`` -> integer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``value`` converted to an integer (from a big endian
representation).

.. doctest::

    >>> from eth_utils import big_endian_to_int
    >>> big_endian_to_int(b'\x00')
    0
    >>> big_endian_to_int(b'\x01')
    1
    >>> big_endian_to_int(b'\x01\x00')
    256

``int_to_big_endian(value)`` -> bytes
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``value`` converted to the big endian representation.

.. doctest::

    >>> from eth_utils import int_to_big_endian
    >>> int_to_big_endian(0)
    b'\x00'
    >>> int_to_big_endian(1)
    b'\x01'
    >>> int_to_big_endian(256)
    b'\x01\x00'

Exceptions
~~~~~~~~~~

``ValidationError``
^^^^^^^^^^^^^^^^^^^

An exception that is raised when something does not pass a validation check.

Functional Utils
~~~~~~~~~~~~~~~~

``compose(*callables)`` -> callable
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    **DEPRECATED** in 0.3.0.

Returns a single function which is the composition of the given
callables.

::

    >>> def f(v):
    ...     return v * 3
    ...
    >>> def g(v):
    ...     return v + 2
    ...
    >>> def h(v):
    ...     return v % 5
    ...
    >>> compose(f, g, h)(1)
    0
    >>> h(g(f(1)))
    0
    >>> compose(f, g, h)(2)
    3
    >>> h(g(f(1)))
    3
    >>> compose(f, g, h)(3)
    1
    >>> h(g(f(1)))
    1
    >>> compose(f, g, h)(4)
    4
    >>> h(g(f(1)))
    4

``flatten_return(callable)`` -> callable() -> tuple
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which performs a non-recursive flattening of the return value
from the given ``callable``.

.. code:: python

    >>> flatten_return(lambda: [[1, 2, 3], [4, 5], [6]])
    (1, 2, 3, 4, 5, 6)

``sort_return(callable)`` => callable() -> tuple
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which sorts the return value from the given ``callable``.

.. code:: python

    >>> flatten_return(lambda: [[1, 2, 3], [4, 5], [6]])
    (1, 2, 3, 4, 5, 6)

``reversed_return(callable)`` => callable() -> tuple
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which reverses the return value from the given ``callable``.

.. code:: python

    >>> reversed_return(lambda: [1, 5, 2, 4, 3])
    (3, 4, 2, 5, 1)

``to_dict(callable)`` => callable() -> dict
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which casts the return value from the given ``callable`` to a
dictionary.

.. doctest::

    >>> from eth_utils import to_dict
    >>> @to_dict
    ... def build_thing():
    ...     yield 'a', 1
    ...     yield 'b', 2
    ...     yield 'c', 3
    ...
    >>> build_thing() == {'a': 1, 'b': 2, 'c': 3}
    True

``to_list(callable)`` => callable() -> list
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which casts the return value from the given ``callable`` to a
list.

.. doctest::

    >>> from eth_utils import to_list
    >>> @to_list
    ... def build_thing():
    ...     yield 'a'
    ...     yield 'b'
    ...     yield 'c'
    ...
    >>> build_thing()
    ['a', 'b', 'c']

``to_ordered_dict(callable)`` => callable() -> collections.OrderedDict
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which casts the return value from the given ``callable`` to an
ordered dictionary of type ``collections.OrderedDict``.

.. doctest::

    >>> from eth_utils import to_ordered_dict
    >>> @to_ordered_dict
    ... def build_thing():
    ...     yield 'd', 4
    ...     yield 'a', 1
    ...     yield 'b', 2
    ...     yield 'c', 3
    ...
    >>> build_thing()
    OrderedDict([('d', 4), ('a', 1), ('b', 2), ('c', 3)])

``to_tuple(callable)`` => callable() -> tuple
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which casts the return value from the given ``callable`` to a
tuple.

.. doctest::

    >>> from eth_utils import to_tuple
    >>> @to_tuple
    ... def build_thing():
    ...     yield 'a'
    ...     yield 'b'
    ...     yield 'c'
    ...
    >>> build_thing()
    ('a', 'b', 'c')

``to_set(callable)`` => callable() -> set
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Decorator which casts the return value from the given ``callable`` to a
set.

.. doctest::

    >>> from eth_utils import to_set
    >>> @to_set
    ... def build_thing():
    ...     yield 'a'
    ...     yield 'b'
    ...     yield 'a'  # duplicate
    ...     yield 'c'
    ...
    >>> build_thing() == {'c', 'b', 'a'}
    True

``apply_to_return_value(callable)`` => decorator_fn
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function takes a single callable and returns a decorator. The
returned decorator, when applied to a function, will incercept the
function’s return value, pass it to the callable, and return the value
returned by the callable.

.. doctest::

    >>> from eth_utils import apply_to_return_value
    >>> double = apply_to_return_value(lambda v: v * 2)
    >>> @double
    ... def f(v):
    ...     return v
    ...
    >>> f(2)
    4
    >>> f(3)
    6

Hexadecimal Utils
~~~~~~~~~~~~~~~~~

``add_0x_prefix(value: HexStr)`` -> HexStr_
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``value`` with a ``0x`` prefix. If the value is already prefixed
it is returned as-is. Value must be a HexStr_.

.. doctest::

    >>> from eth_utils import add_0x_prefix
    >>> from eth_typing import HexStr
    >>> add_0x_prefix(HexStr('12345'))
    '0x12345'
    >>> add_0x_prefix(HexStr('0x12345'))
    '0x12345'

``decode_hex(value)`` -> bytes
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``value`` decoded into a byte string. Accepts any string with or
without the ``0x`` prefix.

.. doctest::

    >>> from eth_utils import decode_hex
    >>> decode_hex('0x123456')
    b'\x124V'
    >>> decode_hex('123456')
    b'\x124V'

``encode_hex(value)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``value`` encoded into a hexadecimal representation with a
``0x`` prefix

.. doctest::

    >>> from eth_utils import encode_hex
    >>> encode_hex(b'\x01\x02\x03')
    '0x010203'

``is_0x_prefixed(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` has a ``0x`` prefix. Value must be a
string literal.

.. doctest::

    >>> from eth_utils import is_0x_prefixed
    >>> is_0x_prefixed('12345')
    False
    >>> is_0x_prefixed('0x12345')
    True

``is_hex(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a hexadecimal encoded string of text
type.

.. doctest::

    >>> from eth_utils import is_hex
    >>> is_hex('')
    False
    >>> is_hex('0x')
    True
    >>> is_hex('0X')
    True
    >>> is_hex('1234567890abcdef')
    True
    >>> is_hex('0x1234567890abcdef')
    True
    >>> is_hex('0x1234567890ABCDEF')
    True
    >>> is_hex('0x1234567890AbCdEf')
    True
    >>> is_hex('12345')  # odd length is ok
    True
    >>> is_hex('0x12345')  # odd length is ok
    True
    >>> is_hex('123456__abcdef')  # non hex characters
    False

    # invalid, will raise TypeError:
    >>> is_hex(b'')
    Traceback (most recent call last):
    TypeError: is_hex requires text typed arguments.
    >>> is_hex(b'0x')
    Traceback (most recent call last):
    TypeError: is_hex requires text typed arguments.
    >>> is_hex(b'0X')
    Traceback (most recent call last):
    TypeError: is_hex requires text typed arguments.

``is_hexstr(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a hexadecimal encoded string of text
type.

.. note::

     This function differs from ``is_hex(value: Any)`` in that it will return
     False on all non-text type arguments, while ``is_hex`` will raise a ``TypeError``
     for all non-text type arguments.

.. doctest::

    >>> from eth_utils import is_hexstr
    >>> is_hexstr('')
    False
    >>> is_hexstr('0x')
    True
    >>> is_hexstr('0X')
    True
    >>> is_hexstr('1234567890abcdef')
    True
    >>> is_hexstr('0x1234567890abcdef')
    True
    >>> is_hexstr('0x1234567890ABCDEF')
    True
    >>> is_hexstr('0x1234567890AbCdEf')
    True
    >>> is_hexstr('12345')  # odd length is ok
    True
    >>> is_hexstr('0x12345')  # odd length is ok
    True
    >>> is_hexstr('123456__abcdef')  # non hex characters
    False
    >>> is_hexstr(b'') # any non-string returns False
    False
    >>> is_hexstr(b'0x') # any non-string returns False
    False

``remove_0x_prefix(value: HexStr)`` -> HexStr_
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``value`` with the ``0x`` prefix stripped. If the value does not
have a ``0x`` prefix it is returned as-is. Value must be a HexStr_.

.. doctest::

    >>> from eth_utils import remove_0x_prefix
    >>> from eth_typing import HexStr
    >>> remove_0x_prefix(HexStr('12345'))
    '12345'
    >>> remove_0x_prefix(HexStr('0x12345'))
    '12345'


Humanize Utils
~~~~~~~~~~~~~~

``humanize_seconds(seconds)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the provide number of seconds as a shorthand string.

.. doctest::

    >>> from eth_utils import humanize_seconds
    >>> humanize_seconds(0)
    '0s'
    >>> humanize_seconds(1)
    '1s'
    >>> humanize_seconds(60)
    '1m'
    >>> humanize_seconds(61)
    '1m1s'


``humanize_bytes(bytes)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the provided byte string in a human readable format.

If the value is 5 bytes or less it is returned in full in its hexadecimal representation (without a ``0x`` prefix)

If the value is longer that 5 bytes it is returned in its hexadecimal
representation (without a ``0x`` prefix) with the middle segment replaced by an
ellipsis, only showing the first and last four hexadecimal nibbles.

.. doctest::

    >>> from eth_utils import humanize_bytes
    >>> humanize_bytes(bytes(range(3)))
     '000102'
    >>> humanize_bytes(bytes(range(5)))
     '0001020304'
    >>> humanize_bytes(bytes(range(32)))
     '0001..1e1f'


``humanize_hexstr(str)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the provided hex string in a human readable format.

If the value is 4 bytes or less it is returned in full in its hexadecimal representation (with a ``0x`` prefix)

If the value is longer than 4 bytes it is returned in its hexadecimal
representation with the middle segment replaced by an
ellipsis, only showing the first and last four hexadecimal nibbles.

.. doctest::

    >>> from eth_utils import humanize_hexstr
    >>> humanize_hexstr('0x1234')
     '0x1234'
    >>> humanize_hexstr('0x12345678')
     '0x12345678'
    >>> humanize_hexstr('0x10203040506070')
     '0x1020..6070'


``humanize_hash(bytes)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

A loose wrapper around ``humanize_bytes`` that is typed specifically for the
``eth_typing.Hash32`` type.

.. doctest::

    >>> from eth_utils import humanize_hash
    >>> humanize_hash(bytes(range(32)))
     '0001..1e1f'


``humanize_integer_sequence(values)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns a concise representation of the provided sequence of integer values.

.. doctest::

    >>> from eth_utils import humanize_integer_sequence
    >>> humanize_integer_sequence((1, 2, 3, 4))
    '1-4'
    >>> humanize_integer_sequence((1, 2, 3, 4, 6, 8, 9, 10))
    '1-4|6|8-10'


``humanize_ipfs_uri(string)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the provided IPFS uri, with the middle segment of the hash replaced by an
ellipsis, only showing the first and last four characters of the hash.

.. doctest::

    >>> from eth_utils import humanize_ipfs_uri
    >>> humanize_ipfs_uri('ipfs://QmTKB75Y73zhNbD3Y73xeXGjYrZHmaXXNxoZqGCagu7r8u')
     'ipfs://QmTK..7r8u'


``humanize_wei(int)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns a human-friendly form of units given an amount of wei.

.. doctest::

    >>> from eth_utils import humanize_wei
    >>> humanize_wei(0)
    '0 wei'
    >>> humanize_wei(1000000000000000000000)
    '1000 ether'
    >>> humanize_wei(9876543)
    '0.009876543 gwei'

Logging Utils
~~~~~~~~~~~~~~


``get_logger(string, [, logger_class]) -> logger``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This API is similar to the standard library ``logging.getLogger`` however, the
logger it returns will be an instance of the provided ``logger_class``.  If
``logger_class`` is not provided this returns an instance of whatever the
current default logger class is set on the ``logging``.


.. doctest::

     >>> import logging
     >>> from eth_utils import get_logger
     >>> logger = get_logger('my_application')
     >>> assert logger.name == 'my_application'
     >>> assert isinstance(logger, logging.getLoggerClass())


``get_extended_debug_logger(string) -> ExtendedDebugLogger``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Like ``get_logger`` except that it always returns an instance of ``ExtendedDebugLogger``


.. doctest::

     >>> from eth_utils import get_extended_debug_logger, ExtendedDebugLogger
     >>> logger = get_extended_debug_logger('my_application')
     >>> assert logger.name == 'my_application'
     >>> assert isinstance(logger, ExtendedDebugLogger), type(logger)



``class HasLogger``
^^^^^^^^^^^^^^^^^^^

Classes which inherit from this class will have an instance of a logger
available on the attribute ``logger``


.. doctest::

     >>> from eth_utils import HasLogger
     >>> class MyClass(HasLogger):
     ...     pass
     ...
     >>> MyClass.logger.debug("This works")
     >>> instance = MyClass()
     >>> instance.logger.debug("This also works")


The ``name`` of the logger instance is derived from the ``__qualname__`` for
the class.

.. warning::

     This class will not behave nicely with the standard library
     ``typing.Generic``.  If you need to create a ``Generic`` class then you'll
     need to assign your logging instances manually.


``class ExtendedDebugLogger``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

A subclass of ``logging.Logger`` which exposes a ``debug2`` function which can
be used to log a message at the ``DEBUG2`` log level.

.. note::

     This class works fine on its own but will produce cleaner logs if you make
     sure to call ``eth_utils.setup_DEBUG2_logging`` at least once before
     issuing any ``debug2`` level logs.


``class HasExtendedDebugLogger``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Same as the ``HasLogger`` class except the logger it exposes is an instance of
``ExtendedDebugLogger``


``setup_DEBUG2_logging() -> None``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Installs the ``DEBUG2`` level to the standard library ``logging`` module which
uses the numeric level of ``8``.  This includes adding it to the known levels
as well as providing a ``logging.DEBUG2`` convenience property on the logging
module.

This function is purely for convenience.  You can use ``ExtendedDebugLogger``
without this, though your logs will be printed with the label ``'Level 8'``.


.. doctest::

     >>> from eth_utils import setup_DEBUG2_logging
     >>> import logging
     >>> logging.getLevelName(8)
     'Level 8'
     >>> setup_DEBUG2_logging()
     >>> logging.getLevelName(8)
     'DEBUG2'
     >>> logging.DEBUG2
     8


.. note::  This function is idempotent


``class HasLoggerMeta``
^^^^^^^^^^^^^^^^^^^^^^^

This is the metaclass which is responsible for adding the logger instance to
the class.  It exposes two additional APIs.

* ``HasLoggerMeta.replace_logger_class(cls: logging.Logger)``

  Returns a new metaclass which will use the provided logger class.


* ``HasLoggerMeta.meta_compat(other: type)``

  Returns a new metaclass that derives from both metaclasses.  This is useful
  when working in conjunction with ``abc.ABC`` or ``typing.Generic``.


``class HasExtendedDebugLoggerMeta``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This metaclass uses the `ExtendedDebugLogger` class, derived from
`HasLoggerMeta.replace_logger_class(ExtendedDebugLogger)`.

Module Loading
~~~~~~~~~~~~~~

``import_string(dotted_path)`` -> Any
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Import a variable/class name for a module given the `dotted_path` string.

Raises an ImportError if the module could not be found.

.. doctest::

    >>> from eth_utils import import_string
    >>> import_string("eth_utils.decorators.combomethod")
    <class 'eth_utils.decorators.combomethod'>

Networks
~~~~~~~~

The :class:`~eth-utils.Networks` class provides methods to obtain network names and
other metadata given a ``chain_id``.

``network_from_chain_id(chain_id)`` -> Network
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the ``Network`` for the given ``chain_id`` int value.

.. doctest::

    >>> from eth_utils import network
    >>> network.network_from_chain_id(1)
    Network(chain_id=1, name='Ethereum Mainnet', shortName='eth', symbol=<ChainId.ETH: 1>)
    >>> network.network_from_chain_id(2)
    Network(chain_id=2, name='Expanse Network', shortName='exp', symbol=<ChainId.EXP: 2>)
    >>> network.network_from_chain_id(100)
    Network(chain_id=100, name='Gnosis', shortName='gno', symbol=<ChainId.GNO: 100>)

``name_from_chain_id(chain_id)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the ``name`` of the ``Network`` with the given ``chain_id`` int value.

.. doctest::

    >>> from eth_utils import network
    >>> network.name_from_chain_id(1)
    'Ethereum Mainnet'
    >>> network.name_from_chain_id(2)
    'Expanse Network'
    >>> network.name_from_chain_id(100)
    'Gnosis'

``short_name_from_chain_id(chain_id)`` -> string
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the ``short_name`` of the ``Network`` with the given ``chain_id`` int value.

.. doctest::

    >>> from eth_utils import network
    >>> network.short_name_from_chain_id(1)
    'eth'
    >>> network.short_name_from_chain_id(2)
    'exp'
    >>> network.short_name_from_chain_id(100)
    'gno'

Numeric Utils
~~~~~~~~~~~~~

``clamp(lower_bound, upper_bound, value)`` -> result
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``value`` clamped within the inclusive range defined by ``[lower_bound,
upper_bound]``.  The value can be any number type that supports ``<`` and ``>``
comparisons against the provided bounds.

.. doctest::

    >>> from eth_utils import clamp
    >>> clamp(5, 7, 4)
    5
    >>> clamp(5, 7, 5)
    5
    >>> clamp(5, 7, 6)
    6
    >>> clamp(5, 7, 7)
    7
    >>> clamp(5, 7, 8)
    7


Type Utils
~~~~~~~~~~

``is_boolean(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is of type ``bool``

.. doctest::

    >>> from eth_utils import is_boolean
    >>> is_boolean(True)
    True
    >>> is_boolean(False)
    True
    >>> is_boolean(1)
    False

``is_bytes(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a byte string or a byte array.

.. doctest::

    >>> from eth_utils import is_bytes
    >>> is_bytes('abcd')
    False
    >>> is_bytes(b'abcd')
    True
    >>> is_bytes(bytearray((1, 2, 3)))
    True

``is_dict(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a mapping type.

.. doctest::

    >>> from eth_utils import is_dict
    >>> is_dict({'a': 1})
    True
    >>> is_dict([1, 2, 3])
    False

``is_integer(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is an integer

.. doctest::

    >>> from eth_utils import is_integer
    >>> is_integer(0)
    True
    >>> is_integer(1)
    True
    >>> is_integer('1')
    False
    >>> is_integer(1.1)
    False

``is_list_like(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a non-string sequence such as a
sequence (such as a list or tuple).

.. doctest::

    >>> from eth_utils import is_list_like
    >>> is_list_like('abcd')
    False
    >>> is_list_like([])
    True
    >>> is_list_like(tuple())
    True

``is_list(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a non-string sequence such as a list.

.. doctest::

    >>> from eth_utils import is_list
    >>> is_list('abcd')
    False
    >>> is_list([])
    True
    >>> is_list(tuple())
    False

``is_tuple(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a non-string sequence such as a tuple.

.. doctest::

    >>> from eth_utils import is_tuple
    >>> is_tuple('abcd')
    False
    >>> is_tuple([])
    False
    >>> is_tuple(tuple())
    True

``is_null(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is ``None``

.. doctest::

    >>> from eth_utils import is_null
    >>> is_null(None)
    True
    >>> is_null(False)
    False

``is_number(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is numeric

.. doctest::

    >>> from eth_utils import is_number
    >>> is_number(1)
    True
    >>> is_number(1.1)
    True
    >>> is_number('1')
    False
    >>> from decimal import Decimal
    >>> is_number(Decimal('1'))
    True

``is_string(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is of any string type.

.. doctest::

    >>> from eth_utils import is_string
    >>> is_string('abcd')
    True
    >>> is_string(b'abcd')
    True
    >>> is_string(bytearray((1, 2, 3)))
    True

``is_text(value)`` -> bool
^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns ``True`` if ``value`` is a text string.

.. doctest::

    >>> from eth_utils import is_text
    >>> is_text(u'abcd')
    True
    >>> is_text(b'abcd')
    False
    >>> is_text(bytearray((1, 2, 3)))
    False
