Customers who bought products a and b but not c

# Table: Customers
# 
# +---------------------+---------+
# | Column Name         | Type    |
# +---------------------+---------+
# | customer_id         | int     |
# | customer_name       | varchar |
# +---------------------+---------+
# customer_id is the column with unique values for this table.
# customer_name is the name of the customer.
# 
#  
# 
# Table: Orders
# 
# +---------------+---------+
# | Column Name   | Type    |
# +---------------+---------+
# | order_id      | int     |
# | customer_id   | int     |
# | product_name  | varchar |
# +---------------+---------+
# order_id is the column with unique values for this table.
# customer_id is the id of the customer who bought the product "product_name".
# 
#  
# 
# Write a solution to report the customer_id and customer_name of customers who bought products "A", "B" but did not buy the product "C" since we want to recommend them to purchase this product.
# 
# Return the result table ordered by customer_id.
# 
# The result format is in the following example.
#
# Example 1:
# Input:
# Customers table:
# +-------------+---------------+
# | customer_id | customer_name |
# +-------------+---------------+
# | 1           | Daniel        |
# | 2           | Diana         |
# | 3           | Elizabeth     |
# | 4           | Jhon          |
# +-------------+---------------+
# Orders table:
# +------------+--------------+---------------+
# | order_id   | customer_id  | product_name  |
# +------------+--------------+---------------+
# | 10         |     1        |     A         |
# | 20         |     1        |     B         |
# | 30         |     1        |     D         |
# | 40         |     1        |     C         |
# | 50         |     2        |     A         |
# | 60         |     3        |     A         |
# | 70         |     3        |     B         |
# | 80         |     3        |     D         |
# | 90         |     4        |     C         |
# +------------+--------------+---------------+
# Output:
# +-------------+---------------+
# | customer_id | customer_name |
# +-------------+---------------+
# | 3           | Elizabeth     |
# +-------------+---------------+
# Explanation: Only the customer_id with id 3 bought the product A and B but not the product C.

import pandas as pd

def find_customers(customers: pd.DataFrame, orders: pd.DataFrame) -> pd.DataFrame:
  products_per_customer = orders.groupby('customer_id')['product_name'].apply(set).reset_index()
  bought_a_b_not_c = products_per_customer[
    products_per_customer['product_name'].apply(lambda x: 'A' in x and 'B' in x and 'C' not in x)
  ]
  result = bought_a_b_not_c.merge(customers, on='customer_id')
  return result[['customer_id', 'customer_name']].sort_values('customer_id')