code: def check( state_engine, nameop, block_id, checked_ops ):
      
  
      namespace_id = nameop['namespace_id']
      sender = nameop['sender']
  
      # must have been revealed
      if not state_engine.is_namespace_revealed( namespace_id ):
         log.warning("Namespace '%s' is not revealed" % namespace_id )
         return False
  
      # must have been sent by the same person who revealed it
      revealed_namespace = state_engine.get_namespace_reveal( namespace_id )
      if revealed_namespace['recipient'] != sender:
         log.warning("Namespace '%s' is not owned by '%s' (but by %s)" % (namespace_id, sender, revealed_namespace['recipient']))
         return False
  
      # can't be ready yet
      if state_engine.is_namespace_ready( namespace_id ):
         # namespace already exists
         log.warning("Namespace '%s' is already registered" % namespace_id )
         return False
  
      # preserve from revealed 
      nameop['sender_pubkey'] = revealed_namespace['sender_pubkey']
      nameop['address'] = revealed_namespace['address']
  
      # can commit imported nameops
      return True
docs: Verify the validity of a NAMESPACE_READY operation.
      It is only valid if it has been imported by the same sender as
      the corresponding NAMESPACE_REVEAL, and the namespace is still
      in the process of being imported.