text: """
  © https://sudipghimire.com.np
  
  create a classes Rectangle, Circle and Box and add respective attributes eg.: radius, length, width, height
  
  for Rectangle, create methods to find out:
      perimeter
      area
      length of diagonal
  
  for Circle, create methods to find out:
      circumference
      area
      diameter
  
  for Box, create methods to find out:
      surface area
      volume
  """
  
  # answer
  