added functino to get content from database

code/database.py

@@ -169,4 +169,10 @@ def insert_list(username_list, timestamp_list, content_list):
                 }
                 dt.insert(val_dict)
             except Exception as e:
-                logging.warning(e)
+                logging.warning(e)
+
+def get_content():
+    with Data_table() as dt:
+        query = f'SELECT * FROM {dt._name} ORDER BY time DESC '
+        df = pd.read_sql_query(query, dt.con)
+    return df['content']