def __call__(self, node, parent):
def cost_to_root(node):<EOL><INDENT>if (node is not None):<EOL><INDENT>return cost_to_parent(node, st[node]) + cost_to_root(st[node])<EOL><DEDENT>else:<EOL><INDENT>return <NUM_LIT:0><EOL><DEDENT><DEDENT>def cost_to_parent(node, parent):<EOL><INDENT>if (parent is not None):<EOL><INDENT>return gr.edge_weight((parent, node))<EOL><DEDENT>else:<EOL><INDENT>return <NUM_LIT:0><EOL><DEDENT><DEDENT>gr = self.graph<EOL>st = self.spanning_tree<EOL>cost =  cost_to_parent(node, parent) + cost_to_root(parent)<EOL>if (cost <= self.radius):<EOL><INDENT>return True<EOL><DEDENT>else:<EOL><INDENT>return False<EOL><DEDENT>
Decide if the given node should be included in the search process.

@type  node: node
@param node: Given node.

@type  parent: node
@param parent: Given node's parent in the spanning tree.

@rtype: boolean
@return: Whether the given node should be included in the search process.