code: def send_event(self, instance, message, event_type=None, time=None,
                     severity='info', source=None, sequence_number=None):
          
          req = rest_pb2.CreateEventRequest()
          req.message = message
          req.severity = severity
          if event_type:
              req.type = event_type
          if time:
              req.time = to_isostring(time)
          if source:
              req.source = source
          if sequence_number is not None:
              req.sequence_number = sequence_number
  
          url = '/archive/{}/events'.format(instance)
          self.post_proto(url, data=req.SerializeToString())
docs: Post a new event.
  
          :param str instance: A Yamcs instance name.
          :param str message: Event message.
          :param Optional[str] event_type: Type of event.
  
          :param severity: The severity level of the event. One of ``info``,
                           ``watch``, ``warning``, ``critical`` or ``severe``.
                           Defaults to ``info``.
          :type severity: Optional[str]
  
          :param time: Time of the event. If unspecified, defaults to mission time.
          :type time: Optional[~datetime.datetime]
  
          :param source: Source of the event. Useful for grouping events in the
                         archive. When unset this defaults to ``User``.
          :type source: Optional[str]
  
          :param sequence_number: Sequence number of this event. This is primarily
                                  used to determine unicity of events coming from
                                  the same source. If not set Yamcs will
                                  automatically assign a sequential number as if
                                  every submitted event is unique.
          :type sequence_number: Optional[int]