Numpy's documentation uses several custom extensions to Sphinx.

The following extensions are available:

* numpydoc: support for the Numpy docstring format in Sphinx, and
  add the code description directives np:function, np-c:function,
  etc. that support the Numpy docstring syntax.
* numpydoc.traitsdoc: For gathering documentation about Traits
  attributes.
* numpydoc.plot_directive: Adaptation of Matplotlib's plot::
  directive. Note that this implementation may still undergo severe
  changes or eventually be deprecated.

Homepage:
https://github.com/numpy/numpydoc
