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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_relationship_cell_val(self, obj, column):
 """ Return the value to insert in a relationship cell Handle the case of complex related datas we want to handle """

        val = SqlaExporter._get_relationship_cell_val(self, obj, column)
        if val == "":
            related_key = column.get('related_key', None)

            if column['__col__'].uselist and related_key is None and \
                    self.is_root:

                # on récupère les objets liés
                key = column['key']
                related_objects = getattr(obj, key, None)
                if not related_objects:
                    return ""
                else:
                    exporter = self._get_related_exporter(
                        related_objects[0],
                        column,
                    )
                    for rel_obj in related_objects:
                        exporter.add_row(rel_obj)

        return val