ลูกค้าที่มีกรมธรรม์ระบุไว้มากที่สุดชื่ออะไร?
What is the name of the customer who has the most policies listed?
df_customers = pd.DataFrame(columns=['customer_name', 'customer_id']); df_customers_policies = pd.DataFrame(columns=['customer_id'])
df_customers.set_index('customer_id').loc[df_customers_policies['customer_id'].value_counts().idxmax(), 'customer_name']