Update app.py

app.py

@@ -201,7 +201,7 @@ def create_collection_name(filepath):
 def build_qa_chain(collection_name, vector_db, file: str, llm_option, temperature, max_tokens, top_k, progress=gr.Progress()):
     print("in build_qa_chain="+file.name) 
 
-    if not file:
+    if file == None:
         raise gr.Error("Please upload a PDF first!")
         
     documents, file_name = process_file2(file)
@@ -376,7 +376,7 @@ def build_qa_chain(collection_name, vector_db, file: str, llm_option, temperatur
 def get_response(collection_name, vector_db, qa_chain, history, query, file):
     #vincent added
     set_apikey(api_key)
-    #print("in get_response count=" + str(app.count))
+    print("in get_response count=" + str(app.count))
     if not file:
         raise gr.Error(message="Upload a PDF")