code: async def prev(self, count=None):
          
          if self._prev_uri is None:
              return self[:0]  # An empty slice of `self`.
          else:
              return self._fetch(self._prev_uri, count)
docs: Load the previous (older) page/batch of events.
  
          :param count: A limit on the number of events to fetch. By default the
              limit is the same as that specified for this set of events.