ระบุรายชื่อแผนกต่างๆ ที่แพทย์บางคนสังกัดอยู่เป็นหลัก
List the names of departments where some physicians are primarily affiliated with.
df_affiliated_with = pd.DataFrame(columns=['department']); df_department = pd.DataFrame(columns=['name', 'departmentid'])
df_department[df_department['departmentid'].isin(df_affiliated_with['department'])]['name']