# Terry: “Sherry is guilty , and Barry is innocent”.
# Sherry: “If Terry is guilty , then so is Barry”.
# Barry: “’Im innocent , but at least one of the others is guilty”.

# Anybody who is innocent told the truth.
# Anybody who is guilty lied. 

from z3 import *

T_guilty = Bool('T_guilty')
S_guilty = Bool('S_guilty')
B_guilty = Bool('B_guilty')

T_innocent = Bool('T_innocent')
S_innocent = Bool('S_innocent')
B_innocent = Bool('B_innocent')

T_consistent = T_guilty == Not(T_innocent)
S_consistent = S_guilty == Not(S_innocent)
B_consistent = B_guilty == Not(B_innocent)

T_truthful = T_innocent == And(S_guilty, B_innocent)
S_truthful = S_innocent == Implies(T_guilty, B_guilty)
B_truthful = B_innocent == And(B_innocent, Or(T_guilty, S_guilty))

constraints = []
constraints += [T_consistent, S_consistent, B_consistent]
constraints += [T_truthful, S_truthful, B_truthful]

s = Solver()
s.add(constraints)