gistfile1.txt

import logic

# Write problem 3 into a logic base.
prob3 = logic.PropKB()
A, B, C, D, E = logic.expr('A, B, C, D, E')
prob3.tell(A)
prob3.tell(~A | C)
prob3.tell(C | ~D)
prob3.tell(D | C)
prob3.tell(~B | ~D | E)

# Use the knowledge to find the answers to (3.1) and (3.2)
print(prob3.ask_if_true(C)) # True
print(prob3.ask_if_true(E)) # False