text: #!/usr/bin/env python
  
  ### Example purdy library code
  #
  # Demonstrates the slide transition animation
  
  from purdy.actions import Append, Wait, Transition, Fold
  from purdy.content import Code
  from purdy.ui import SimpleScreen, VirtualCodeBox
  
  screen = SimpleScreen(starting_line_number=10)
  code_box = screen.code_box
  blob = Code('../display_code/simple.repl')
  blob2 = Code('../display_code/traceback.repl')
  blob3 = Code('../display_code/decorator.repl')
  
  vbox = VirtualCodeBox(starting_line_number=20, display_mode='urwid')
  
  # prep vbox for copy
  vbox.perform_actions([
      Append(vbox, blob3),
      Fold(vbox, 2, 2),
  ])
  
  actions = [
      Append(code_box, blob2),
      Wait(),
      Transition(code_box),     # test transition to empty
      Append(code_box, blob),
      Wait(),
  
      # Test Wait after Transition and code box copy
      Transition(code_box, code_box_to_copy=vbox),
      Wait(),
      Append(code_box, blob2),
  ]
  
  if __name__ == '__main__':
      screen.run(actions)
  