python - python中嵌套字典的换行代码

Question

用新的Entity Resolution在 Alexa 中，嵌套字典变得非常嵌套。引用深层嵌套值的最 pythonic 方式是什么？我如何编写每行 79 个字符以内的代码？

这是我目前拥有的，虽然它有效，但我很确定有更好的方法:

if 'VolumeQuantity' in intent['slots']:
    if 'resolutions' in intent['slots']['VolumeQuantity']:
        half_decibels = intent['slots']['VolumeQuantity']['resolutions']['resolutionsPerAuthority'][0]['values'][0]['value']['name'].strip()
    elif 'value' in intent['slots']['VolumeQuantity']:
        half_decibels = intent['slots']['VolumeQuantity']['value'].strip()

这是来自 alexa 的 json 的部分示例

  {
    "type": "IntentRequest",
    "requestId": "amzn1.echo-api.request.9a...11",
    "timestamp": "2018-03-28T20:37:21Z",
    "locale": "en-US",
    "intent": {
      "name": "RelativeVolumeIntent",
      "confirmationStatus": "NONE",
      "slots": {
        "VolumeQuantity": {
          "name": "VolumeQuantity",
          "confirmationStatus": "NONE"
        },
        "VolumeDirection": {
          "name": "VolumeDirection",
          "value": "softer",
          "resolutions": {
            "resolutionsPerAuthority": [
              {
                "authority": "amzn1.er-authority.echo-blah-blah-blah",
                "status": {
                  "code": "ER_SUCCESS_MATCH"
                },
                "values": [
                  {
                    "value": {
                      "name": "down",
                      "id": "down"
                    }
                  }
                ]
              }
            ]
          },
          "confirmationStatus": "NONE"
        }
      }
    },
    "dialogState": "STARTED"
  }

Answer 1

您可能指的是嵌套字典，列表只接受整数索引。

无论如何，(ab？)在括号内使用隐含的行延续，我认为这是非常可读的:

>>> d = {'a':{'b':{'c':'value'}}}
>>> (d
...     ['a']
...     ['b']
...     ['c']
... )
'value'

或者替代地

>>> (d['a']
...   ['b']
...   ['c'])
'value'