Add __str__ methods to TLMessage and MessageContainer

telethon/tl/message_container.py

@@ -16,6 +16,10 @@ class MessageContainer(TLObject):
             '<Ii', MessageContainer.CONSTRUCTOR_ID, len(self.messages)
         ) + b''.join(bytes(m) for m in self.messages)
 
+    def __str__(self):
+        return 'MessageContainer(messages=[{}])'\
+            .format(', '.join(str(m) for m in self.messages))
+
     @staticmethod
     def iter_read(reader):
         reader.read_int(signed=False)  # code

telethon/tl/tl_message.py

@@ -15,3 +15,7 @@ class TLMessage(TLObject):
     def __bytes__(self):
         body = GzipPacked.gzip_if_smaller(self.request)
         return struct.pack('<qii', self.msg_id, self.seq_no, len(body)) + body
+
+    def __str__(self):
+        return 'TLMessage(msg_id={}, seq_no={}, body={})'\
+            .format(self.msg_id, self.seq_no, self.request)