code: def location(self):
          
          if self._location is None:
              self._location = "{}/{}-{}".format(
                  self.stream,
                  self.type,
                  self.sequence,
              )
          return self._location
docs: Return a string uniquely identifying the event.
  
          This string can be used to find the event in the event store UI (cf. id
          attribute, which is the UUID that at time of writing doesn't let you
          easily find the event).