text: class Combinations:
      def __init__(self, elements, num):
          self.elements = elements
          self.slots = elements[:num]
  
      def solve(self, index, start=0):
          if index >= len(self.slots):
              print(self.slots)
  
          else:
              for i in range(start, len(self.elements)):
                  self.slots[index] = self.elements[i]
                  self.solve(index + 1, i)
  
  
  permute = Combinations(['A', 'B', 'C'], 2)
  permute.solve(0)
  