- Home
- Get it
- Docs
- Extend/Develop

# Example Google Style Python Docstrings

See also

Example NumPy Style Python Docstrings

Download: `example_google.py`

    # -*- coding: utf-8 -*-
    """Example Google style docstrings.

    This module demonstrates documentation as specified by the `Google Python
    Style Guide`_. Docstrings may extend over multiple lines. Sections are created
    with a section header and a colon followed by a block of indented text.

    Example:
        Examples can be given using either the ``Example`` or ``Examples``
        sections. Sections support any reStructuredText formatting, including
        literal blocks::

            $ python example_google.py

    Section breaks are created by resuming unindented text. Section breaks
    are also implicitly created anytime a new section starts.

    Attributes:
        module_level_variable1 (int): Module level variables may be documented in
            either the ``Attributes`` section of the module docstring, or in an
            inline docstring immediately following the variable.

            Either form is acceptable, but the two should not be mixed. Choose
            one convention to document module level variables and be consistent
            with it.

    Todo:
        * For module TODOs
        * You have to also use ``sphinx.ext.todo`` extension

    .. _Google Python Style Guide:
       http://google.github.io/styleguide/pyguide.html

    """

    module_level_variable1 = 12345

    module_level_variable2 = 98765
    """int: Module level variable documented inline.

    The docstring may span multiple lines. The type may optionally be specified
    on the first line, separated by a colon.
    """

    def module_level_function(param1, param2=None, *args, **kwargs):
        """This is an example of a module level function.

        Function parameters should be documented in the ``Args`` section. The name
        of each parameter is required. The type and description of each parameter
        is optional, but should be included if not obvious.

        Parameter types -- if given -- should be specified according to
        `PEP 484`_, though `PEP 484`_ conformance isn't required or enforced.

        If \*args or \*\*kwargs are accepted,
        they should be listed as ``*args`` and ``**kwargs``.

        The format for a parameter is::

            name (type): description
                The description may span multiple lines. Following
                lines should be indented. The "(type)" is optional.

                Multiple paragraphs are supported in parameter
                descriptions.

        Args:
            param1 (int): The first parameter.
            param2 (Optional[str]): The second parameter. Defaults to None.
                Second line of description should be indented.
            *args: Variable length argument list.
            **kwargs: Arbitrary keyword arguments.

        Returns:
            bool: True if successful, False otherwise.

            The return type is optional and may be specified at the beginning of
            the ``Returns`` section followed by a colon.

            The ``Returns`` section may span multiple lines and paragraphs.
            Following lines should be indented to match the first line.

            The ``Returns`` section supports any reStructuredText formatting,
            including literal blocks::

                {
                    'param1': param1,
                    'param2': param2
                }

        Raises:
            AttributeError: The ``Raises`` section is a list of all exceptions
                that are relevant to the interface.
            ValueError: If `param2` is equal to `param1`.

        .. _PEP 484:
           https://www.python.org/dev/peps/pep-0484/

        """
        if param1 == param2:
            raise ValueError('param1 may not be equal to param2')
        return True

    def example_generator(n):
        """Generators have a ``Yields`` section instead of a ``Returns`` section.

        Args:
            n (int): The upper limit of the range to generate, from 0 to `n` - 1.

        Yields:
            int: The next number in the range of 0 to `n` - 1.

        Examples:
            Examples should be written in doctest format, and should illustrate how
            to use the function.

            >>> print([i for i in example_generator(4)])
            [0, 1, 2, 3]

        """
        for i in range(n):
            yield i

    class ExampleError(Exception):
        """Exceptions are documented in the same way as classes.

        The __init__ method may be documented in either the class level
        docstring, or as a docstring on the __init__ method itself.

        Either form is acceptable, but the two should not be mixed. Choose one
        convention to document the __init__ method and be consistent with it.

        Note:
            Do not include the `self` parameter in the ``Args`` section.

        Args:
            msg (str): Human readable string describing the exception.
            code (Optional[int]): Error code.

        Attributes:
            msg (str): Human readable string describing the exception.
            code (int): Exception error code.

        """

        def __init__(self, msg, code):
            self.msg = msg
            self.code = code

    class ExampleClass(object):
        """The summary line for a class docstring should fit on one line.

        If the class has public attributes, they may be documented here
        in an ``Attributes`` section and follow the same formatting as a
        function's ``Args`` section. Alternatively, attributes may be documented
        inline with the attribute's declaration (see __init__ method below).

        Properties created with the ``@property`` decorator should be documented
        in the property's getter method.

        Attribute and property types -- if given -- should be specified according
        to `PEP 484`_, though `PEP 484`_ conformance isn't required or enforced.

        Attributes:
            attr1 (str): Description of `attr1`.
            attr2 (Optional[int]): Description of `attr2`.

        .. _PEP 484:
           https://www.python.org/dev/peps/pep-0484/

        """

        def __init__(self, param1, param2, param3):
            """Example of docstring on the __init__ method.

            The __init__ method may be documented in either the class level
            docstring, or as a docstring on the __init__ method itself.

            Either form is acceptable, but the two should not be mixed. Choose one
            convention to document the __init__ method and be consistent with it.

            Note:
                Do not include the `self` parameter in the ``Args`` section.

            Args:
                param1 (str): Description of `param1`.
                param2 (Optional[int]): Description of `param2`. Multiple
                    lines are supported.
                param3 (List[str]): Description of `param3`.

            """
            self.attr1 = param1
            self.attr2 = param2
            self.attr3 = param3  #: Doc comment *inline* with attribute

            #: List[str]: Doc comment *before* attribute, with type specified
            self.attr4 = ['attr4']

            self.attr5 = None
            """Optional[str]: Docstring *after* attribute, with type specified."""

        @property
        def readonly_property(self):
            """str: Properties should be documented in their getter method."""
            return 'readonly_property'

        @property
        def readwrite_property(self):
            """List[str]: Properties with both a getter and setter should only
            be documented in their getter method.

            If the setter method contains notable behavior, it should be
            mentioned here.
            """
            return ['readwrite_property']

        @readwrite_property.setter
        def readwrite_property(self, value):
            value

        def example_method(self, param1, param2):
            """Class methods are similar to regular functions.

            Note:
                Do not include the `self` parameter in the ``Args`` section.

            Args:
                param1: The first parameter.
                param2: The second parameter.

            Returns:
                True if successful, False otherwise.

            """
            return True

        def __special__(self):
            """By default special members with docstrings are not included.

            Special members are any methods or attributes that start with and
            end with a double underscore. Any special member with a docstring
            will be included in the output, if
            ``napoleon_include_special_with_doc`` is set to True.

            This behavior can be enabled by changing the following setting in
            Sphinx's conf.py::

                napoleon_include_special_with_doc = True

            """
            pass

        def __special_without_docstring__(self):
            pass

        def _private(self):
            """By default private members are not included.

            Private members are any methods or attributes that start with an
            underscore and are *not* special. By default they are not included
            in the output.

            This behavior can be changed such that private members *are* included
            by changing the following setting in Sphinx's conf.py::

                napoleon_include_private_with_doc = True

            """
            pass

        def _private_without_docstring(self):
            pass