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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 add_meta(self, name, value):
 """ Add a pair of meta data to the definition :param name: name of the meta :type name: str :param value: value of the meta :type value: str """

        for mt in self.metas:
            if mt.name == name:
                mt.value = value
                return self
        self.metas.append(MetaDef(name, value))
        return self