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pythonlambda

How to access values of two keys in the map lambda function

I have a list of dictionary like below :

    sample = [{'By': {'email': '[email protected]', 'name': 'xyzzy', 'id': '5859'}},{'By': {'email': '[email protected]', 'name': 'abccb', 'id': '9843'}},
{'By': {'email': '[email protected]', 'name': 'xyzzy', 'id': '5859'}}]

From this, I am trying to access keys 'name' and 'id' and write distinct values into a dictionary.
Below is returning id's alone :

print(set(map(lambda x: x['By']['id'], sample)))

output: {'9843', '5859'}

Required output : {"9843":"abccb", "5859":"xyzzy"}

I tried with f-string to concatenate the 'id' and 'name' values with a colon (:) in between to give in the format "id:name" for each dictionary item in the list.

set(map(lambda x: f"{x['By']['id']}:{x['By']['name']}", sample))

output : {'9843:abccb', '5859:xyzzy'}

Is it possible to access values of two keys in the map lambda function ? Thank you.

Solution

  • You want a dict, not a set. You can get all the values in the lambda and pack them in a tuple

    print(dict(map(lambda x: (x['By']['id'], x['By']['name']), sample)))

    You should also consider a simpler solution, you don't really need map and lambda here, dict-comprehensions will do just fine

    print({x['By']['id']: x['By']['name'] for x in sample})