Update ppt_chunker.py

ppt_chunker.py

@@ -65,10 +65,10 @@ def ppt_chunk(file_like, model):
                         list_items = list_items - duplicate
 
                     current_chunk.append("\n".join(list_items))
-                    list_items.clear()
+                    list_items = set()
 
                 chunks.append([elem.id, current_chunk])
-                current_chunk.clear()
+                current_chunk = []
                 print(f'NEW CHUNK: {chunks[-1]}')
         else:
             if elem.text[-1] in NON_ENDING_PUNCT: