text: import usb.core
  import usb.util
  import time
  
  # find our device
  dev = usb.core.find(idVendor=0x726c, idProduct=0x3101)
  
  # was it found?
  if dev is None:
      raise ValueError('Device not found')
  
  # set the active configuration. With no arguments, the first
  # configuration will be the active one
  dev.reset()
  
  dev.set_configuration()
  
  # get an endpoint instance
  cfg = dev.get_active_configuration()
  intf = cfg[(0,0)]
  usb.util.claim_interface(dev, intf)
  
  
  ep = usb.util.find_descriptor(
      intf,
      # match the first OUT endpoint
      custom_match = \
      lambda e: \
          usb.util.endpoint_direction(e.bEndpointAddress) == \
          usb.util.ENDPOINT_OUT)
  
  assert ep is not None
  
  
  epin = usb.util.find_descriptor(
      intf,
      # match the first OUT endpoint
      custom_match = \
      lambda e: \
          usb.util.endpoint_direction(e.bEndpointAddress) == \
          usb.util.ENDPOINT_IN)
  
  assert epin is not None
  ep.write(b'\xf0')
  usb.util.release_interface(dev, intf)
  