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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def validate(idText, alpha, r, cert, caPubkey):
 """ A server can validate an implicit certificate response using identity string @idText, private value @alpha (used to generate cert request), and the certificate response @r (private key component) and implicit @cert. @raises Exception if the certificate response is invalid. @returns (privkey, pubkey) """

    # Verify parameter types
    assertScalarType(alpha)
    assertScalarType(r)
    assertType(cert, ec1Element)
    assertType(caPubkey, ec1Element)

    G = generatorEc()

    # Compute the private key @s
    e = _exp(cert, idText)
    s = (e*alpha + r) % orderEc()

    # Compute the public key two ways: using the privkey and using the cert
    # (the way a client will compute it)
    # The easy way
    S1 = s*G

    # Using the cert
    S2 = e*cert + caPubkey

    # The two techniques should produce the same pubkey value -- raise an
    # exception if they don't match
    if S1 != S2:
        raise Exception("Implicit certification response failed validation")
    return s, S1