#NEWLINE# def accept( self , visitor ) : #NEWLINE# #INDENT# for i in range ( len ( self . children ) ) : #NEWLINE# #INDENT# if isinstance ( self . children [ i ] , QNode ) : #NEWLINE# #INDENT# self . children [ visitor ] = self . children [ i ] . accept ( visitor ) #NEWLINE# #UNINDENT# #UNINDENT# return visitor . visit_combination ( self )