Docstring inheritance fails under Python 3

[pstoeckl]

When pdoc (v0.3.2, running under Python 3) is run on the following minimal example:

class A:
    x = 1
    """One class var"""

    y = 2
    """Another class var"""

class B(A):
    x = 5
    y = 10

it fails to correctly register the inherited docstrings for class B.

In particular, exactly one of B.x or B.y (either has been observed) will have its docstring correctly inherited from the corresponding member of A, and the other will not.