Parameters
    ----------
    attr_list : list
        A list of (keyword, value) tuple pairs
    global_attrs : tuple(list, dict)
        Global attributes which update the local attributes

def get_attr(attr_list, global_attrs):
    """
    Parameters
    ----------
    attr_list : list
        A list of (keyword, value) tuple pairs
    global_attrs : tuple(list, dict)
        Global attributes which update the local attributes
    """
    local_attr = [], {}
    for kv in attr_list:
        keyword = kv[0]
        if len(kv) == 1:
            local_attr[0].append(keyword)
            continue
        elif len(kv) == 2:
            value = kv[1]
        elif len(kv) > 2:
            value = kv[1:]

        if keyword == 'tag':
            local_attr[1].setdefault(keyword, set()).add(value)
        else:
            local_attr[1][keyword] = value

    attr0 = copy.copy(global_attrs[0])
    attr1 = copy.copy(global_attrs[1])

    if local_attr[0]:
        attr0.extend(local_attr[0])

    if local_attr[1]:
        attr1.update(local_attr[1])

    return attr0, attr1