text: # Copyright 1996-2021 Cyberbotics Ltd.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  from controller import Robot, Node
  
  robot = Robot()
  
  timestep = int(robot.getBasicTimeStep())
  
  print('LEDS:')
  for d in range(robot.getNumberOfDevices()):
      device = robot.getDeviceByIndex(d)
      if device.getNodeType() == Node.LED:
          print(device.getName())
          device.set(1)
  
  while robot.step(timestep) != -1:
      pass
  