Currently, pydocstyle warns by default when a function docstring is followed by a blank line (D202). However, a careful reading of PEP257 indicates that this rule should only apply to one-line docstrings, not to multiline docstrings: the sole sentence regarding this, "There's no blank line either before or after the docstring.", occurs in the "One-line docstrings" section, immediately after the "The closing quotes are on the same line as the opening quotes. This looks better for one-liners." sentence which clearly only applies to one-line docstrings. Allowing an empty line after the function docstring also makes sense if e.g. the function body contains empty lines: in something like

def func():
    """
    Some docstring.

    Some more stuff.
    """
    do_this()
    do_that()

    do_this_again()
    do_that_again()

if there's no empty line after the docstring, I personally feel the docstring "binds" too closely to the first part of the body at the expense of the second part.