#NEWLINE# def do_OP_TUCK( stack ) : #NEWLINE# #INDENT# '\n    >>> s = [1, 2, 3]\n    >>> do_OP_TUCK(s)\n    >>> print(s)\n    [1, 3, 2, 3]\n    ' #NEWLINE# v1 = stack . pop ( ) #NEWLINE# v2 = stack . pop ( ) #NEWLINE# stack . append ( v1 ) #NEWLINE# stack . append ( v2 ) #NEWLINE# stack . append ( v1 )