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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 raise_sigint():
 """ Raising the SIGINT signal in the current process and all sub-processes. os.kill() only issues a signal in the current process (without subprocesses). CTRL+C on the console sends the signal to the process group (which we need). """

    if hasattr(signal, 'CTRL_C_EVENT'):
        # windows. Need CTRL_C_EVENT to raise the signal in the whole process group
        os.kill(os.getpid(), signal.CTRL_C_EVENT)
    else:
        # unix.
        pgid = os.getpgid(os.getpid())
        if pgid == 1:
            os.kill(os.getpid(), signal.SIGINT)
        else:
            os.killpg(os.getpgid(os.getpid()), signal.SIGINT)