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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 short_doc(self):
 """Gets the "short" documentation of a command. By default, this is the :attr:`brief` attribute. If that lookup leads to an empty string then the first line of the :attr:`help` attribute is used instead. """

        if self.brief is not None:
            return self.brief
        if self.help is not None:
            return self.help.split('\n', 1)[0]
        return ''