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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 from_dict(self, mapdict):
 """ Import the attribute map from a dictionary :param mapdict: The dictionary """


        self.name_format = mapdict["identifier"]
        try:
            self._fro = dict(
                [(k.lower(), v) for k, v in mapdict["fro"].items()])
        except KeyError:
            pass
        try:
            self._to = dict([(k.lower(), v) for k, v in mapdict["to"].items()])
        except KeyError:
            pass

        if self._fro is None and self._to is None:
            raise ConverterError("Missing specifications")

        if self._fro is None or self._to is None:
            self.adjust()