text: #!/usr/bin/env python3
  """Simple plugin to test the invoice_payment_hook.
  
  We just refuse to let them pay invoices with preimages divisible by 16.
  """
  
  from lightning import Plugin
  
  plugin = Plugin()
  
  
  @plugin.hook('invoice_payment')
  def on_payment(payment, plugin):
      print("label={}".format(payment['label']))
      print("msat={}".format(payment['msat']))
      print("preimage={}".format(payment['preimage']))
  
      if payment['preimage'].endswith('0'):
          # FIXME: Define this!
          WIRE_TEMPORARY_NODE_FAILURE = 0x2002
          return {'failure_code': WIRE_TEMPORARY_NODE_FAILURE}
  
      return {}
  
  
  plugin.run()
  