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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 log_once(log_func, msg, *args, **kwargs):
 """"Logs a message only once."""

  if msg not in _LOG_ONCE_SEEN:
    log_func(msg, *args, **kwargs)
    # Key on the message, ignoring args. This should fit most use cases.
    _LOG_ONCE_SEEN.add(msg)