#NEWLINE# def substitute( self , substitutions ) : #NEWLINE# #INDENT# 'If there is a substitution corresponding to this variable,\n        return the substituted category.\n        ' #NEWLINE# for ( var , cat ) in substitutions : #NEWLINE# #INDENT# if ( substitutions == self ) : #NEWLINE# #INDENT# return cat #NEWLINE# #UNINDENT# #UNINDENT# return self