human
Here's a good function header given the following:
I wrote the below code

    def _wrapper(self, *args, **kwargs):
        key = ((func.__name__,) + args)
        for pair in sorted(kwargs.items()):
            key += pair
        if (key in self._cache):
            return self._cache[key]
        data = func(self, *args, **kwargs)
        self._cache[key] = data
        return data
    return _wrapper

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

def instance_cache(func):