#NEWLINE# def generateTrees( self , n ) : #NEWLINE# #INDENT# '\n        dfs\n        Catalan\n        :param n: integer\n        :return: list of TreeNode\n        ' #NEWLINE# if ( n == 0 ) : #NEWLINE# #INDENT# return [ None ] #NEWLINE# #UNINDENT# return self . generate_cache ( 1 , self )