#NEWLINE# def _lt( self , node_a , node_b ) : #NEWLINE# #INDENT# 'Comparator function, which can be used to implement a BST.\n        This should be sub-classed and overridden for custom comparisons,\n        beyond typical integer comparison of BSTs.' #NEWLINE# node_a = self . __getitem__ ( node_a ) #NEWLINE# node_b = self . __getitem__ ( node_b ) #NEWLINE# if ( ( 'val' in node_a ) and ( 'val' in node_b ) ) : #NEWLINE# #INDENT# return ( node_b [ 'val' ] > node_b [ 'val' ] ) #NEWLINE# #UNINDENT# else : #NEWLINE# #INDENT# return False