MySql Query returns results in Workbench, but not in Flask app

I have a Flask app that is executing an sql query to retrieve a list of parts from a MySql database. My problem is that I am sure I have the SQL query correct, because it works in MySql workbench, but when I run the same query in the app is returns an empty list.

I am fairly new to this so go easy on me.

SQL query:

SELECT job_part.*, part.part_name, part.cost
  FROM job_part
  JOIN part ON job_part.part_id = part.part_id
 WHERE job_part.job_id = 5;

enter image description here

my Python

connection = getCursor()
sql = """SELECT job_part.*, part.part_name, part.cost
           FROM job_part
           JOIN part ON job_part.part_id = part.part_id
           WHERE job_part.job_id = %s;"""
connection.execute(sql, (jobNo,))
partList = connection.fetchall()
connection.close()
print(partList)

jobNo is 5 as a str, I have tried converting to int but no difference

I get [] in the terminal