human
I wrote the below code

    @extension.make_extension(trigger=(1, 'epoch'), priority=extension.PRIORITY_WRITER)
    def _observe_value(trainer):
        trainer.observation[observation_key] = target_func(trainer)
    return _observe_value

What's a good function header?

Here's a good function header?
assistant
#Here's a good function header.

def observe_value(observation_key, target_func):