Python - 动态构建嵌套树

Question

我正在尝试使用 python 构建树层次结构，可以说我有他的结构，我需要能够动态添加更多子级，例如 Bannana。 我觉得我的问题有点不清楚

更新：我需要创建一个这样的结构，但是值会改变，所以我需要创建函数来传递一个 int 并创建 Apple(Children) 的数量并做同样的事情为柠檬和所有其他孩子。苹果节点也是根节点。

Apple
   Bannana
   Lemon
      Juice
        Drink
   Watermelon
       Red
         Round

但是我可以有一个完全不同的结构，例如

Apple
   Bannana
   Lemon
      Juice
        Drink
          Watermelon
       Red
          Round

Json 输出将是

{
    'Apple': 'Fruit',
    'children': [{
        'Bannana': 'fruit',
        'children': None
    },  {
        'Lemon': 'Fruit',
        'children': [{
            'Juice': 'Food',
            'children': [{
                'Drink': 'Action',
                'children': None
             And so on...

如何使层次结构动态化？例如特定父级下的行数？

我已经从我找到的示例中尝试过类似的方法

import collections
def add_element(root, path, data):
    if len(path) == 1:
        root[path[0]] = data
    else:
        add_element(root[path[0]], path[1:], data)

count = 1


tree = lambda: collections.defaultdict(tree)
root = tree()
n= 10
for i in range(1,n):
    path_list= ['Apple', 'Lemon', 'Juice' + str(count)]
    print (path_list)
    count += 1
    add_element(root,path_list, 1 )
print (root)

编辑 1

根据答案，我稍微修改了代码

args = {'Apple': 'Apple', 'Lemon': 'Lemon', 'Juice': 'Juice', 'Drink': 'Drink'}

s = """
{Apple}
   {Lemon}
      {Juice}
         {Drink}
""".format(**args)

def group_data(vals):
  if len(vals) == 1:
     return {vals[0]:'Fruit', 'Children':None}
  new_data = [list(b) for _, b in itertools.groupby(vals, key=lambda x:bool(re.findall('^\s', x)))]
  new_group = [[new_data[i], new_data[i+1]] for i in range(0, len(new_data), 2)]
  result = []
  for a, b in new_group:
     result.extend([{i:'Fruit', 'Children':None} for i in a[:-1]])
     result.append({a[-1]:'Fruit', 'Children':group_data([re.sub('^\s{3}', '', c) for c in b])})
  return result

_new_data = [i.strip('\n') for i in filter(None, s.split('\n'))]


print(json.dumps(group_data(_new_data), indent=4))

这工作正常，但它仍然是硬编码的，这不是我想要的。

Answer 1

您可以分析每个水果之前的空白：

s = """
Apple
   Bannana
   Lemon
      Juice
         Drink
            Watermelon
      Red
         Round
"""

---

import itertools, re
def group_data(vals):
  if len(vals) == 1:
     return {vals[0]:'Fruit', 'Children':None}
  new_data = [list(b) for _, b in itertools.groupby(vals, key=lambda x:bool(re.findall('^\s', x)))]
  new_group = [[new_data[i], new_data[i+1]] for i in range(0, len(new_data), 2)]
  result = []
  for a, b in new_group:
     result.extend([{i:'Fruit', 'Children':None} for i in a[:-1]])
     result.append({a[-1]:'Fruit', 'Children':group_data([re.sub('^\s{3}', '', c) for c in b])})
  return result

_new_data = [i.strip('\n') for i in filter(None, s.split('\n'))]

---

import json
print(json.dumps(group_data(_new_data), indent=4))

输出：

[
     {
       "Apple": "Fruit",
       "Children": [
         {
            "Bannana": "Fruit",
            "Children": null
           },
           {
               "Lemon": "Fruit",
               "Children": [
                  {
                      "Juice": "Fruit",
                       "Children": [
                            {
                             "Drink": "Fruit",
                             "Children": {
                                 "Watermelon": "Fruit",
                                 "Children": null
                              }
                          }
                      ]
                  },
                  {
                       "Red": "Fruit",
                       "Children": {
                          "Round": "Fruit",
                          "Children": null
                     }
                  }
              ]
          }
       ]
    }
]