def test_equal():
 assert (Q.positive(x) == Q.positive(x))
 assert (Q.positive(x) != (~ Q.positive(x)))
 assert ((~ Q.positive(x)) == (~ Q.positive(x)))

def test_equal ( ) : assert ( Q . positive ( x ) == Q . positive ( x ) ) assert ( Q . positive ( x ) != ( ~ Q . positive ( x ) ) ) assert ( ( ~ Q . positive ( x ) ) == ( ~ Q . positive ( x ) ) )
test for equality .