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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 backtrace_on_usr1 ():
 """Install a signal handler such that this program prints a Python traceback upon receipt of SIGUSR1. This could be useful for checking that long-running programs are behaving properly, or for discovering where an infinite loop is occurring. Note, however, that the Python interpreter does not invoke Python signal handlers exactly when the process is signaled. For instance, a signal delivered in the midst of a time.sleep() call will only be seen by Python code after that call completes. This means that this feature may not be as helpful as one might like for debugging certain kinds of problems. """

    import signal
    try:
        signal.signal (signal.SIGUSR1, _print_backtrace_signal_handler)
    except Exception as e:
        warn ('failed to set up Python backtraces on SIGUSR1: %s', e)