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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 notify_init(self):
        ''' run the queed callback  for just the first session only '''
        _session_count = len(self._sessions)
        self._update_session_count(1, _session_count)
        if _session_count == 1:
            self._run_queued_callbacks()