Python decorator to add objects to __all__

public.py

def public(f):
    """Use a decorator to avoid retyping function/class names. [#]_
    
    * Based on an idea by Duncan Booth:
      http://groups.google.com/group/comp.lang.python/msg/11cbb03e09611b8a
    * Improved via a suggestion by Dave Angel:
      http://groups.google.com/group/comp.lang.python/msg/3d400fb22d8a42e1
    
    References:
    .. [#] https://stackoverflow.com/questions/6206089/is-it-a-good-practice-to-add-names-to-all-using-a-decorator
    
    Args:
        f (object): Object to be set
    
    Returns:
        object: Decorated object
    """
    all = sys.modules[f.__module__].__dict__.setdefault('__all__', [])
    if f.__name__ not in all:  # Prevent duplicates if run from an IDE.
        all.append(f.__name__)
    return f