Make sure to explicitly close opened files.

    except ImportError as e:

        if os.path.basename(os.getcwd()) != part:

            raise e

    finally:

        if f:

            f.close()

    while parts:

        part = parts.pop()

        f, path, descr = imp.find_module(part, path and [path] or None)

        if f:

            f.close()

    return path

def load_command_class(app_name, name):