PlanarEmbedding.add_half_edge_first# PlanarEmbedding.add_half_edge_first(start_node, end_node)[source]# Add a half-edge and set end_node as start_node’s leftmost neighbor. The new edge is inserted counterclockwise with respect to the current leftmost neighbor, if there is one. Parameters: start_nodenode end_nodenode See also add_half_edge connect_components