human
Complete this python program:
def _meijergexpand(func, z0, allow_hyper=False, rewrite='default', place=None):
assistant
#Here is the Python program you requested.

    """Try to find an expression for the Meijer G function specified
    by the G_Function ``func``. If ``allow_hyper`` is True, then returning
    an expression in terms of hypergeometric functions is allowed.
    Currently this just does Slater\s theorem.
    If expansions exist both at zero and at infinity, ``place``
    can be set to ``0`` or ``zoo`` for the preferred choice.
    """
    global _meijercollection
    if (_meijercollection is None):
        _meijercollection = MeijerFormulaCollection()
    if (rewrite == 'default'):
        rewrite = None
    func0 = func
    debug('Try    to    expand    Meijer    G    function    corresponding    to    ', func)
    z = Dummy('z')
    (func, ops) = reduce_order_meijer(func)
    if ops:
        debug('        Reduced    order    to    ', func)
    else:
        debug('        Could    not    reduce    order.')
    f = _meijercollection.lookup_origin(func)
    if (f is not None):
        debug('        Found    a    Meijer    G    formula:    ', f.func)
        ops += devise_plan_meijer(f.func, func, z)
        C = apply_operators(f.C.subs(f.z, z), ops, make_derivative_operator(f.M.subs(f.z, z), z))
        C = C.applyfunc(make_simp(z))
        r = (C * f.B.subs(f.z, z))
        r = r[0].subs(z, z0)
        return powdenest(r, polar=True)
    debug("        Could    not    find    a    direct    formula.    Trying    Slater's    theorem.")
    def can_do(pbm, pap):
        '    Test    if    slater    applies.    '
        for i in pbm:
            if (len(pbm[i]) > 1):
                l = 0
                if (i in pap):
                    l = len(pap[i])
                if ((l + 1) < len(pbm[i])):
                    return False
        return True
    def do_slater(an, bm, ap, bq, z, zfinal):
        func = G_Function(an, bm, ap, bq)
        (_, pbm, pap, _) = func.compute_buckets()
        if (not can_do(pbm, pap)):
            return (S(0), False)
        cond = ((len(an) + len(ap)) < (len(bm) + len(bq)))
        if ((len(an) + len(ap)) == (len(bm) + len(bq))):
            cond = (abs(z) < 1)
        if (cond is False):
            return (S(0), False)
        res = S(0)
        for m in pbm:
            if (len(pbm[m]) == 1):
                bh = pbm[m][0]
                fac = 1
                bo = list(bm)
                bo.remove(bh)
                for bj in bo:
                    fac *= gamma((bj - bh))
                for aj...