def get_related_field(self):
        data = self.to._meta.get_field_by_name(self.field_name)
        if not data[2]:
            raise FieldDoesNotExist("No related field named '%s'" %
                    self.field_name)
        return data[0]
Returns the Field in the 'to' object to which this relationship is
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.5/django/db/models/fields/related.py/ManyToOneRel.get_related_field