text: #!/usr/bin/python3
  
  with open('./input.txt', 'r') as input:
      list_numbers = input.read().splitlines()
      list_numbers = [int(item) for item in list_numbers]
      for i in range(len(list_numbers)):
          for compare_number in list_numbers[i:len(list_numbers)]:
              if int(list_numbers[i]) + int(compare_number) == 2020:
                  print(list_numbers[i]*compare_number)
      
  input.close()