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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 auth(username, password):
    '''
    Try and authenticate
    '''
    try:
        keystone = client.Client(username=username, password=password,
                                 auth_url=get_auth_url())
        return keystone.authenticate()
    except (AuthorizationFailure, Unauthorized):
        return False