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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 are_credentials_still_valid(awsclient):
 """Check whether the credentials have expired. :param awsclient: :return: exit_code """

    client = awsclient.get_client('lambda')
    try:
        client.list_functions()
    except GracefulExit:
        raise
    except Exception as e:
        log.debug(e)
        log.error(e)
        return 1
    return 0