Support NumPy style Python return docs with one or more named variables

[ProGamerGov]

Sphinx should support NumPy style Python return docs with one or more named variables.

For example, see the example below from the following link: https://numpydoc.readthedocs.io/en/latest/format.html#returns

Returns
-------
err_code : int
    Non-zero value indicates error code, or zero on success.
err_msg : str or None
    Human readable error message, or None on success.

Currently, the above formatting is not supported.