Update to always use role user as role system is useless pos.

testing.py

@@ -12,15 +12,15 @@ from helper.token_counter import count_tokens
 
 messages = [
     {
-        "role": "system",
+        "role": "user",
         "content": "You are a IELTS examiner.",
     },
     {
-        "role": "system",
+        "role": "user",
         "content": f"The question you have to grade is of type and is the following: ",
     },
     {
-        "role": "system",
+        "role": "user",
         "content": "Please provide a JSON object response with the overall grade and breakdown grades, "
                    "formatted as follows: {'overall': 7.0, 'task_response': {'Task Achievement': 8.0, "
                    "'Coherence and Cohesion': 6.5, 'Lexical Resource': 7.5, 'Grammatical Range and Accuracy': "