text: # Copyright (c) 2019 BIJU ALE
  
  # Author: BIJU ALE (github.com/BijuAle)
  # License: MIT License
  
  # Permission is hereby granted, free of charge, to any person obtaining
  # a copy of this software and associated documentation files (the
  # "Software"), to deal in the Software without restriction, including
  # without limitation the rights to use, copy, modify, merge, publish,
  # distribute, sublicense, and/or sell copies of the Software, and to
  # permit persons to whom the Software is furnished to do so, subject to
  # the following conditions:
  
  # The above copyright notice and this permission notice shall be
  # included in all copies or substantial portions of the Software.
  
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  
  def checkCart(cart, item):
      for i in cart:
          print(i)
  
      if item in cart:
          print('No need to buy ' + item)
      else:
          print("Buy " + item)
      print("\n")
  
  
  cart = {"cheese", "ham", "sausage", "milk"}
  checkCart(cart, 'ham')
  checkCart(cart, 'oats')
  checkCart(cart, 'honey')
  checkCart(cart, 'cheese')
  
  
  # Set operations can be performed
  set_a = {1, 2, 3, 4, 5}
  set_b = {2, 4, 5, 9}
  
  
  # Intersection
  print(set_a & set_b)
  
  # Difference
  print(set_a - set_b)
  print(set_b - set_a)
  
  # Union
  print(set_a | set_b)
  