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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 error_info():
 """Return information about failed tasks."""

    worker = global_worker
    worker.check_connected()
    return (global_state.error_messages(driver_id=worker.task_driver_id) +
            global_state.error_messages(driver_id=DriverID.nil()))