Python docstrings can be written following several formats as the other posts showed. However the default Sphinx docstring format was not mentioned and is based on reStructuredText (reST). You can get some information about the main formats in that tuto.
Note that the reST is recommended by the PEP 287
There follows the main used formats for docstrings.
Historically a javadoc like style was prevalent, so it was taken as a base for Epydoc (with the called Epytext format) to generate documentation.
Example:
""" This is a javadoc style.
@param param1: this is a first param @param param2: this is a second param @return: this is a description of what is returned @raise keyError: raises an exception """
Nowadays, the probably more prevalent format is the reStructuredText (reST) format that is used by Sphinx to generate documentation. Note: it is used by default in JetBrains PyCharm (type triple quotes after defining a method and hit enter). It is also used by default as output format in Pyment.
Example:
""" This is a reST style.
:param param1: this is a first param :param param2: this is a second param :returns: this is a description of what is returned :raises keyError: raises an exception """
Google has their own format that is often used. It also can be interpreted by Sphinx.
Example:
""" This is an example of Google style.
Args: param1: This is the first param. param2: This is a second param.
Returns: This is a description of what is returned.
Raises: KeyError: Raises an exception. """ Even more examples
Note that Numpy recommend to follow their own numpydoc based on Google format and usable by Sphinx.
""" My numpydoc description of a kind of very exhautive numpydoc format docstring.
first : array_like
the 1st param name first
second :
the 2nd param
third : {'value', 'other'}, optional
the 3rd param, by default 'value'
string a value in a string
KeyError when a key error OtherError when an other error """ Converting/Generating
It is possible to use a tool like Pyment to automatically generate docstrings to a Python project not yet documented, or to convert existing docstrings (can be mixing several formats) from a format to an other one.
Note: The examples are taken from the Pyment documentation