category_iteration

gistfile1.txt

data = [
    {
        "id": 1,
        "parent_id": None,
    },
    {
        "id": 2,
        "parent_id": None,
    },
    {
        "id": 3,
        "parent_id": 1,
    },
    {
        "id": 4,
        "parent_id": 2,
    },
    {
        "id": 5,
        "parent_id": 1,
    },
    {
        "id": 6,
        "parent_id": 3,
    },
    {
        "id": 7,
        "parent_id": 6,
    },
    {
        "id": 8,
        "parent_id": 3,
    },
]


def the_iter(parent_id, children):
    for item in data:
        if item['parent_id'] == parent_id:
            item['children'] = []
            children.append(item)
    for item in children:
        return the_iter(item['id'], item['children'])


if __name__ == '__main__':
    result = []
    the_iter(None, result)
    print result