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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_BF_hypergraph(self):
 """Indicates whether the hypergraph is a BF-hypergraph. A BF-hypergraph consists of only B-hyperedges and F-hyperedges. See "is_B_hypergraph" or "is_F_hypergraph" for more details. :returns: bool -- True iff the hypergraph is an F-hypergraph. """

        for hyperedge_id in self._hyperedge_attributes:
            tail = self.get_hyperedge_tail(hyperedge_id)
            head = self.get_hyperedge_head(hyperedge_id)
            if len(tail) > 1 and len(head) > 1:
                return False
        return True