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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_extension_by_field(self, name):
 """ Find the ParlerOptions object that corresponds with the given translated field. """

        if name is None:
            raise TypeError("Expected field name")

        # Reuse existing lookups.
        tr_model = self.get_model_by_field(name)
        for meta in self._extensions:
            if meta.model == tr_model:
                return meta