def fixup_namespace_packages(path_item, parent=None):
_imp.acquire_lock()<EOL>try:<EOL><INDENT>for package in _namespace_packages.get(parent, ()):<EOL><INDENT>subpath = _handle_ns(package, path_item)<EOL>if subpath:<EOL><INDENT>fixup_namespace_packages(subpath, package)<EOL><DEDENT><DEDENT><DEDENT>finally:<EOL><INDENT>_imp.release_lock()<EOL><DEDENT>
Ensure that previously-declared namespace packages include path_item