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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 item_related_name(self):
 """ The ManyToMany field on the item class pointing to this class. If there is more than one field, this value will be None. """

        if not hasattr(self, '_item_related_name'):
            many_to_many_rels = \
                get_section_many_to_many_relations(self.__class__)
            if len(many_to_many_rels) != 1:
                self._item_related_name = None
            else:
                self._item_related_name = many_to_many_rels[0].field.name
        return self._item_related_name