[python] How to add an element to a list?

From this..

data = json.loads(urlopen('someurl').read())

...I will get:

{'list': [{'a':'1'}]}

I want to add {'b':'2'} into the list.

Any idea how to do it?

This question is related to python json list

The answer is


I would do this:

data["list"].append({'b':'2'})

so simply you are adding an object to the list that is present in "data"


import json

myDict = {'dict': [{'a': 'none', 'b': 'none', 'c': 'none'}]}
test = json.dumps(myDict)
print(test)

{"dict": [{"a": "none", "b": "none", "c": "none"}]}

myDict['dict'].append(({'a': 'aaaa', 'b': 'aaaa', 'c': 'aaaa'}))
test = json.dumps(myDict)
print(test)

{"dict": [{"a": "none", "b": "none", "c": "none"}, {"a": "aaaa", "b": "aaaa", "c": "aaaa"}]}


Elements are added to list using append():

>>> data = {'list': [{'a':'1'}]}
>>> data['list'].append({'b':'2'})
>>> data
{'list': [{'a': '1'}, {'b': '2'}]}

If you want to add element to a specific place in a list (i.e. to the beginning), use insert() instead:

>>> data['list'].insert(0, {'b':'2'})
>>> data
{'list': [{'b': '2'}, {'a': '1'}]}

After doing that, you can assemble JSON again from dictionary you modified:

>>> json.dumps(data)
'{"list": [{"b": "2"}, {"a": "1"}]}'

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