code: def connection_required(func):
          
          @functools.wraps(func)
          def wrapper(self, *args, **kwargs):
              """Wrapper function to check that the given ``JLink`` has been
              connected to a target.
  
              Args:
                self (JLink): the ``JLink`` instance
                args: list of arguments to pass to the wrapped function
                kwargs: key-word arguments dict to pass to the wrapped function
  
              Returns:
                The return value of the wrapped function.
  
              Raises:
                JLinkException: if the JLink's target is not connected.
              """
              if not self.target_connected():
                  raise errors.JLinkException('Target is not connected.')
              return func(self, *args, **kwargs)
          return wrapper
docs: Decorator to specify that a target connection is required in order
          for the given method to be used.
  
          Args:
            func (function): function being decorated
  
          Returns:
            The wrapper function.