910.sagews

var ("x,y")
(X*2+2*y-3*x*y*2-1)

Traceback (most recent call last): File "<stdin>", line 1, in <module> File "_sage_input_4.py", line 6, in <module> exec compile(ur'(X*_sage_const_2 +_sage_const_2 *y-_sage_const_3 *x*y*_sage_const_2 -_sage_const_1 )' + '\n', '', 'single') File "", line 1, in <module> NameError: name 'X' is not defined