python - 属性错误: 'str' object has no attribute 'keys' error in getting json object keys

Question

我正在尝试将 json 对象转换为 csv 文件。当我传递 obj 并打印它时，它工作得很好。但是当我从 #Problem 行继续时，我收到 AttributeError: 'str' object has no attribute 'keys'。我传递了完全相同的对象。如何修复这个错误并让它正常运行？

import json
import csv
import os

def flattenjson( b, delim ):
    val = {}
    for i in b.keys():
        if isinstance( b[i], dict ):
            get = flattenjson( b[i], delim )
            for j in get.keys():
                val[ i + delim + j ] = get[j]
        else:
            val[i] = b[i]
    return val

jjj = {
    "pk": 22,
    "model": "auth.permission",
    "fields": {
      "codename": "add_message",
      "name": "Can add message",
      "content_type": 8
   }
 }

print(flattenjson(jjj , "__" ))
#Problem
input = map( lambda x: flattenjson( x, "__" ), jjj )

columns = [ x for row in input for x in row.keys() ]
columns = list( set( columns ) )

with open( 'sad.csv', 'wb' ) as out_file:
    csv_w = csv.writer( out_file )
    csv_w.writerow( columns )

    for i_r in input:
        csv_w.writerow( map( lambda x: i_r.get( x, "" ), columns ) )

Answer 1

在 lambda 函数中迭代时，您给出唯一被视为字符串的键

因此，以下解决方案可能适合您。

编辑了代码，而不是传递唯一的键作为参数，我传递了一个新的字典。

input = map( lambda x: flattenjson({x: jjj[x]}, "__" ), jjj )