fixed memory leak when session.send coroutine is cancelled (pyrogram#311)

YoilyL · delivrance · commit aa937a704d0b · 2019-09-09T15:56:57.000+02:00
added that when session.send coroutine is cancelled (or if any other exception is raised) the result should still be removed from the results list
diff --git a/pyrogram/session/session.py b/pyrogram/session/session.py
@@ -382,8 +382,8 @@ async def _send(self, data: TLObject, wait_response: bool = True, timeout: float
                 await asyncio.wait_for(self.results[msg_id].event.wait(), timeout)
             except asyncio.TimeoutError:
                 pass
-
-            result = self.results.pop(msg_id).value
+            finally:
+                result = self.results.pop(msg_id).value
 
             if result is None:
                 raise TimeoutError
