Replace .to_bytes() with the special .__bytes__ function

telethon/tl/gzip_packed.py

@@ -13,21 +13,21 @@ class GzipPacked(TLObject):
 
     @staticmethod
     def gzip_if_smaller(request):
-        """Calls request.to_bytes(), and based on a certain threshold,
+        """Calls bytes(request), and based on a certain threshold,
            optionally gzips the resulting data. If the gzipped data is
            smaller than the original byte array, this is returned instead.
 
            Note that this only applies to content related requests.
         """
-        data = request.to_bytes()
+        data = bytes(request)
         # TODO This threshold could be configurable
         if request.content_related and len(data) > 512:
-            gzipped = GzipPacked(data).to_bytes()
+            gzipped = bytes(GzipPacked(data))
             return gzipped if len(gzipped) < len(data) else data
         else:
             return data
 
-    def to_bytes(self):
+    def __bytes__(self):
         # TODO Maybe compress level could be an option
         return struct.pack('<I', GzipPacked.CONSTRUCTOR_ID) + \
                TLObject.serialize_bytes(gzip.compress(self.data))