Reorder the keys in an OrderedDict ``od`` in-place.

def od_reorder_keys(od, keys_in_new_order): # not used
    '''
    Reorder the keys in an OrderedDict ``od`` in-place.
    '''
    if set(od.keys()) != set(keys_in_new_order):
        raise KeyError('Keys in the new order do not match existing keys')
    for key in keys_in_new_order:
        od[key] = od.pop(key)
    return od