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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 is_linguist_lookup(self, lookup):
 """ Returns true if the given lookup is a valid linguist lookup. """

        field = utils.get_field_name_from_lookup(lookup)

        # To keep default behavior with "FieldError: Cannot resolve keyword".
        if (
            field not in self.concrete_field_names
            and field in self.linguist_field_names
        ):
            return True

        return False