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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 The expression tree is very different
Step1:  If XOR(f, g) is UNSAT, functions f and g are equivalent.
But sum bit 9 is a deep expression.
Converting to CNF is impossible, so use backtracking
Step2:  Let's see if we can do better using the Tseitin transformation,
and PicoSAT extension
Step3:  Success!
Verify that both functions returned UNSAT
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Python Code:
%dotobjs S_rca[2].simplify(), S_ksa[2].simplify()
Explanation: The expression tree is very different:
End of explanation
f = Xor(S_rca[9], S_ksa[9])
%timeit f.satisfy_one()
Explanation: If XOR(f, g) is UNSAT, functions f and g are equivalent.
But sum bit 9 is a deep expression.
Converting to CNF is impossible, so use backtracking:
End of explanation
g = f.tseitin()
%timeit g.satisfy_one()
Explanation: Let's see if we can do better using the Tseitin transformation,
and PicoSAT extension:
End of explanation
assert f.satisfy_one() is None and g.satisfy_one() is None
Explanation: Success!
Verify that both functions returned UNSAT:
End of explanation
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