fix session state

app.py

@@ -91,11 +91,12 @@ def check_token_length(text, max_tokens=1024):
 
 import uuid
 def get_user_session(state):
+    if not state:
+        state = {}
     if not state.get("session_id"):
         state["session_id"] = uuid.uuid4().hex
     return state["session_id"]
 
-
 # ---------- Translation Function ----------
 
 def mpc_initial_translate(source_sentence, src_language, tgt_language):
@@ -210,6 +211,8 @@ def mpc_translation(text, src_language, target_language, iterations, session_id)
 
 def process_text(text, src_language, target_language, max_iterations_value, threshold_value,
                  good_ref_contexts_num_value, translation_methods, state):
+    
+    state = state or {}
     session_id = get_user_session(state)
 
     """