คณะวิศวกรรมศาสตร์เปิดสอนกี่ปริญญา?
How many degrees does the engineering department offer?
df_dept = pd.DataFrame(columns=['department_id', 'department_name']); df_degrees = pd.DataFrame(columns=['department_id'])
df_degrees[df_degrees['department_id'].isin(df_dept[df_dept['department_name'] == 'engineer']['department_id'])].count()