นักเรียนที่มีเกรดเฉลี่ยต่ำสุดอยู่ในชื่อภาควิชาอะไร?
What is the department name of the students with lowest gpa belongs to?
df_student = pd.DataFrame(columns=['dept_code', 'stu_gpa']); df_department = pd.DataFrame(columns=['dept_name', 'dept_code'])
df_department[df_department['dept_code'].isin(df_student[df_student['stu_gpa'] == df_student['stu_gpa'].min()]['dept_code'])]['dept_name']