Issue #7425: Refactor test_pydoc test case for '-k' behavior and add new test cases for importing bad packages and unreadable packages dirs.
Issue #7425: Refactor test_pydoc test case for '-k' behavior and add
new test cases for importing bad packages and unreadable packages dirs.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator