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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def doc_sub(*sub):
 """ Decorator for performing substitutions in docstrings. Using @doc_sub(some_note, other_note) on a function with {0} and {1} in the docstring will substitute the contents of some_note and other_note for {0} and {1}, respectively. Decorator appears to work properly both with IPython help (tab completion and ?) and with Sphinx. """

    def dec(obj):
        obj.__doc__ = obj.__doc__.format(*sub)
        return obj
    return dec