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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 get_uservar(self, user, name):
 """Get a variable about a user. :param str user: The user ID to look up a variable for. :param str name: The name of the variable to get. :return: The user variable, or ``None`` or ``"undefined"``: * If the user has no data at all, this returns ``None``. * If the user doesn't have this variable set, this returns the string ``"undefined"``. * Otherwise this returns the string value of the variable. """

        if name == '__lastmatch__':  # Treat var `__lastmatch__` since it can't receive "undefined" value
            return self.last_match(user)
        else:
            return self._session.get(user, name)