human
I wrote the below code

    (left, rest, right) = intersperse_pat.match(string).groups()
    def reverse(s):
        return s[::(-1)]
    splits = split(reverse(rest), counts)
    res = separator.join(map(reverse, reverse(splits)))
    return (((left + res) + right), (((len(splits) > 0) and (len(splits) - 1)) or 0))

What's a good function header?

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

def intersperse(string, counts, separator=''):