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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 dlog(msg, log_path=DEFAULT_LOG_PATH):
 """A handy log utility for debugging multi-process, multi-threaded activities."""

  with open(log_path, 'a') as f:
    f.write('\n{}@{}: {}'.format(os.getpid(), threading.current_thread().name, msg))