human
I wrote the below code

    if (not (fixed is None)):
        raise NotImplementedError
    nobs = np.sum(freq)
    lnnobsfact = special.gammaln((nobs + 1))
    def nloglike(params):
        'negative    loglikelihood    function    of    binned    data\n\n                                corresponds    to    multinomial\n                                '
        prob = np.diff(distfn.cdf(binedges, *params))
        return (- (lnnobsfact + np.sum(((freq * np.log(prob)) - special.gammaln((freq + 1))))))
    return optimize.fmin(nloglike, start)

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

def fitbinned(distfn, freq, binedges, start, fixed=None):