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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_field_serializable(self, field_name):
 """Return True if the field can be serialized into a JSON doc."""

        return (
            self._meta.get_field(field_name).get_internal_type()
            in self.SIMPLE_UPDATE_FIELD_TYPES
        )