提取從JSON特定值在Python

Question

我已經從呼叫的結果在Python JSON對象到一個API（使用的urllib2）生成如下：

results = urllib2.urlopen(req).read() 
json1 = json.loads(results) 

此生成包含類似的東西JSON對象以下（由於截斷大小）：

"http://d.opencalais.com/dochash-1/895ba8ff-4c32-3ae1-9615-9a9a9a1bcb39/cat/1":{ 
    "_typeGroup":"topics", 
    "category":"http://d.opencalais.com/cat/Calais/Entertainment_Culture", 
    "classifierName":"Calais", 
    "categoryName":"Entertainment_Culture", 
    "score":1 
}, 
"http://d.opencalais.com/genericHasher-1/b6a2d07d-133b-35ad-85e2-54d524e750cf":{ 
    "_typeGroup":"entities", 
    "_type":"TVShow", 
    "name":"Hard Knocks", 
    "_typeReference":"http://s.opencalais.com/1/type/em/e/TVShow", 
    "instances":[ 
      { 
      "detection":"[ New York Jets during the summer of 2010 on HBO's ]Hard Knocks[.\n]", 
      "prefix":" New York Jets during the summer of 2010 on HBO's ", 
      "exact":"Hard Knocks", 
      "suffix":".\n", 
      "offset":135, 
      "length":11 
      } 
    ], 
    "relevance":0.5 
}, 

"http://d.opencalais.com/genericHasher-1/802a1ebb-7fac-354f-b02f-6ef8442950d3":{ 
    "_typeGroup":"entities", 
    "_type":"Organization", 
    "name":"New York Jets", 
    "organizationtype":"sports", 
    "nationality":"American", 
    "_typeReference":"http://s.opencalais.com/1/type/em/e/Organization", 
    "instances":[ 
      { 
      "detection":"[ Tebow caught a few training camp glimpses of the ]New York Jets[ during the summer of 2010 on HBO's Hard]", 
      "prefix":" Tebow caught a few training camp glimpses of the ", 
      "exact":"New York Jets", 
      "suffix":" during the summer of 2010 on HBO's Hard", 
      "offset":86, 
      "length":13 
      } 
    ], 
    "relevance":0.5 
} 

從這個JSON，我想提取「_type」和「名」僅在「typeGroup」 ==「實體」。

例如，對於上面的JSON對象的輸出應該是這樣的：

TVShow: Hard Knocks 
Organization: New York Jets. 

可能有人請就如何做到這一點在Python幫助嗎？

[UPDATE 1]

基於來自Jatin答案我嘗試以下：

for key,value in json1.items(): 
    if value["_typeGroup"] == "entities": 
     print value['_type'], value['name'] 

然而，這導致錯誤KeyError異常： '_typeGroup'

我試圖看如何按鍵和值打印如下：

for key,value in json1.items(): 
    print key,value 

這導致下面的輸出（表示只是一個鍵，值對）：

http://d.opencalais.com/genericHasher-1/802a1ebb-7fac-354f-b02f-6ef8442950d3 {u'_typeReference': u'http://s.opencalais.com/1/type/em/e/Organization', u'_type': u'Organization', u'name': u'New York Jets', u'_typeGroup': u'entities', u'instances': [{u'suffix': u" during the summer of 2010 on HBO's Hard", u'prefix': u' Tebow caught a few training camp glimpses of the ', u'detection': u"[ Tebow caught a few training camp glimpses of the ]New York Jets[ during the summer of 2010 on HBO's Hard]", u'length': 13, u'offset': 86, u'exact': u'New York Jets'}], u'relevance': 0.5, u'nationality': u'American', u'organizationtype': u'sports'} 

這似乎是一個嵌套JSON。所以我嘗試了以下按如下方式訪問內部鍵值對：

for key,value in json1.items(): 
    val1 = value 
    for key,value in val1.items(): 
     if value["_typeGroup"] == "entities": 
      print value['_type'], value['name'] 

然而，它引發以下錯誤：

TypeError: string indices must be integers 

Answer 1

我想你會得到這個錯誤，因爲你的JSON中的某些值沒有_typeGroup。試試這個：

for key,value in x.items(): 
    if value.get("_typeGroup", "") == "entities": 
     print value['_type'], value['name'] 

Answer 2

for key,value in json1.items(): 
    if value.get('typeGroup') == "entities": 
     print value.get('_type'), value.get('name') 

試試這個，讓我知道。 IT應該工作。