code: async def whowas(self, nickname):
          
          # Same treatment as nicknames in whois.
          if protocol.ARGUMENT_SEPARATOR.search(nickname) is not None:
              result = self.eventloop.create_future()
              result.set_result(None)
              return result
  
          if nickname not in self._pending['whowas']:
              await self.rawmsg('WHOWAS', nickname)
              self._whowas_info[nickname] = {}
  
              # Create a future for when the WHOWAS requests succeeds.
              self._pending['whowas'][nickname] = self.eventloop.create_future()
  
          return await self._pending['whowas'][nickname]
docs: Return information about offline user.
          This is an blocking asynchronous method: it has to be called from a coroutine, as follows:
  
              info = await self.whowas('Nick')