[RFE] Support container members type specification using square brackets

[radekholy24]

Please add a support for specifying types of members of containers/iterables/sequences/mappings/iterators/generators.
Use case:
Imagine that there is a function that accepts only mappings from str to list of ints. The docstring would look like:

def foo(map):
    """Bar

    :param map: a mapping
    :type map: collections.abc.Mapping[str, list[int]]

    """

Such a syntax is already supported by e.g. PyCharm.