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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 write_pid(pidfile):
 """Write processID to the pidfile. Notice: It exits main program if it fails to write pidfile. Arguments: pidfile (str):
 pidfile to update """

    pid = str(os.getpid())
    try:
        with open(pidfile, mode='w') as _file:
            print("writing processID {p} to pidfile".format(p=pid))
            _file.write(pid)
    except OSError as exc:
        sys.exit("failed to write pidfile:{e}".format(e=exc))