def update_func_meta (fake_func, real_func):
    """Set meta information (eg. __doc__) of fake function to that
    of the real function.
    @return fake_func
    """
    fake_func.__module__ = real_func.__module__
    fake_func.__name__ = real_func.__name__
    fake_func.__doc__ = real_func.__doc__
    fake_func.__dict__.update(real_func.__dict__)
    return fake_func
Set meta information (eg. __doc__) of fake function to that
    of the real function.
    @return fake_func