human
I wrote the below code

    _inv_error = 'cannot    get    an    analytical    solution    for    the    inversion'
    uflags = dict(check=False, simplify=False)
    def _cov(p, e):
        if cov:
            (oldp, olde) = cov
            if (Poly(e, p).degree(p) in (1, 2)):
                cov[:] = [p, olde.subs(oldp, _solve(e, p, **uflags)[0])]
            else:
                raise NotImplementedError
        else:
            cov[:] = [p, e]
    def _canonical(eq, cov):
        if cov:
            (p, e) = cov
            rep = {p: Dummy(p.name)}
            eq = eq.xreplace(rep)
            cov = [p.xreplace(rep), e.xreplace(rep)]
        eq = factor_terms(_mexpand(eq.as_numer_denom()[0], recursive=True), clear=True)
        if eq.is_Mul:
            args = []
            for f in eq.args:
                if f.is_number:
                    continue
                if (f.is_Pow and _take(f, True)):
                    args.append(f.base)
                else:
                    args.append(f)
            eq = Mul(*args)
        free = eq.free_symbols
        if (len(free) == 1):
            if eq.coeff((free.pop() ** degree(eq))).could_extract_minus_sign():
                eq = (- eq)
        elif eq.could_extract_minus_sign():
            eq = (- eq)
        return (eq, cov)
    def _Q(pow):
        c = pow.as_base_exp()[1].as_coeff_Mul()[0]
        if (not c.is_Rational):
            return S.One
        return c.q
    def _take(d, take_int_pow):
        for pow in Mul.make_args(d):
            if (not (pow.is_Symbol or pow.is_Pow)):
                continue
            (b, e) = pow.as_base_exp()
            if (not b.has(*syms)):
                continue
            if ((not take_int_pow) and (_Q(pow) == 1)):
                continue
            free = pow.free_symbols
            if free.intersection(syms):
                return True
        return False
    _take = flags.setdefault('_take', _take)
    (cov, nwas, rpt) = [flags.setdefault(k, v) for (k, v) in sorted(dict(cov=[], n=None, rpt=0).items())]
    eq =...

What's a good function header?

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

def unrad(eq, *syms, **flags):