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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 full_name(self):
 """ Obtains the full name of the actor. :return: the full name :rtype: str """

        if self._full_name is None:
            fn = self.name.replace(".", "\\.")
            parent = self._parent
            if parent is not None:
                fn = parent.full_name + "." + fn
            self._full_name = fn

        return self._full_name