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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 XOR(a, b, exc=CertifierValueError('Expected at least one certified value')):
 """ Only one arg must not raise a Certifier exception when called overall. Raise the specified exception on failure. :params Certifier a: The first certifiers to call :params Certifier b: The second certifiers to call :param Exception exc: Callable that is raised if XOR fails. """

    errors = []

    for certifier in [a, b]:
        try:
            certifier()
        except CertifierError as e:
            errors.append(e)

    if len(errors) != 1:
        if exc is not None:
            raise exc