def extender(self, edge):
(j, k, B, _, _) = edge<EOL>for (i, j, A, alpha, B1b) in self.chart[j]:<EOL><INDENT>if B1b and B == B1b[<NUM_LIT:0>]:<EOL><INDENT>self.add_edge([i, k, A, alpha + [edge], B1b[<NUM_LIT:1>:]])<EOL><DEDENT><DEDENT>
See what edges can be extended by this edge.