docs: def delete_edge_by_id(self, edge_id):
          """Removes the edge identified by "edge_id" from the graph."""
          edge = self.get_edge(edge_id)
  
          # Remove the edge from the "from node"
          # --Determine the from node
          from_node_id = edge['vertices'][0]
          from_node = self.get_node(from_node_id)
  
          # --Remove the edge from it
          from_node['edges'].remove(edge_id)
  
          # Remove the edge from the "to node"
          to_node_id = edge['vertices'][1]
          to_node = self.get_node(to_node_id)
  
          # --Remove the edge from it
          to_node['edges'].remove(edge_id)
  
          # Remove the edge from the edge list
          del self.edges[edge_id]
  
          self._num_edges -= 1