from operator import *

a = -1
b = 5

print('a =', a)
print('b =', b)
print()

print('not_(a)     :', not_(a))
print('truth(a)    :', truth(a))
print('is_(a, b)   :', is_(a, b))
print('is_not(a, b):', is_not(a, b))
