--- a/libervia/backend/plugins/plugin_xep_0047.py	Tue Jun 18 12:06:45 2024 +0200
+++ b/libervia/backend/plugins/plugin_xep_0047.py	Wed Jun 19 18:44:57 2024 +0200
@@ -155,7 +155,7 @@
         return session_data
 
     def _on_ibb_open(self, iq_elt, client):
-        """"Called when an IBB <open> element is received
+        """ "Called when an IBB <open> element is received
 
         @param iq_elt(domish.Element): the whole <iq> stanza
         """
@@ -192,13 +192,15 @@
         # FIXME: if we never get the events, the observers stay.
         #        would be better to have generic observer and check id once triggered
         client.xmlstream.addObserver(event_data, observer_cb, client=client)
-        client.xmlstream.addOnetimeObserver(event_close, self._on_ibb_close, client=client)
+        client.xmlstream.addOnetimeObserver(
+            event_close, self._on_ibb_close, client=client
+        )
         # finally, we send the accept stanza
         iq_result_elt = xmlstream.toResponse(iq_elt, "result")
         client.send(iq_result_elt)
 
     def _on_ibb_close(self, iq_elt, client):
-        """"Called when an IBB <close> element is received
+        """ "Called when an IBB <close> element is received
 
         @param iq_elt(domish.Element): the whole <iq> stanza
         """
@@ -287,7 +289,9 @@
             self._kill_session(sid, client, error_condition)
         client.send(iq_elt)
 
-    def start_stream(self, client, stream_object, local_jid, to_jid, sid, block_size=None):
+    def start_stream(
+        self, client, stream_object, local_jid, to_jid, sid, block_size=None
+    ):
         """Launch the stream workflow
 
         @param stream_object(ifaces.IStreamProducer): stream object to send
@@ -340,7 +344,9 @@
             data_elt.addContent(base64.b64encode(buffer_).decode())
             args = [session_data, client]
             d = next_iq_elt.send()
-            d.addCallbacks(self._iq_data_stream_cb, self._iq_data_stream_eb, args, None, args)
+            d.addCallbacks(
+                self._iq_data_stream_cb, self._iq_data_stream_eb, args, None, args
+            )
         else:
             self.terminate_stream(session_data, client)