How to change dictionary keys in a list of dictionaries?

Question

Given the following list of dictionaries:

[
     {'Label': 'Acura', 'Value': '1'}, 
     {'Label': 'Agrale', 'Value': '2'}
]

How can I replace the word 'Label' with 'Make' and 'Value' with 'Code'?

I´m new to python and have tried many different approaches with no success.

Hi Hugo, could you please add the code of your "different approaches" at least one approach. It will make your question more clearer, please also what you expect as output. — Dani Mesejo, Feb 11 '19 at 19:38

score 16 · Accepted Answer · answered Feb 11 '19 at 19:42

Use .pop:

lst = [{'Label': 'Acura', 'Value': '1'}, {'Label': 'Agrale', 'Value': '2'}]

for d in lst:
    d['Make'] = d.pop('Label')
    d['Code'] = d.pop('Value')

print(lst)

This yields

[{'Make': 'Acura', 'Code': '1'}, {'Make': 'Agrale', 'Code': '2'}]

If the key happens to not exist. you could define a default key as well:

d['new_key'] = d.pop('missing_key', 'default_value')

score 4 · Answer 2 · answered Feb 11 '19 at 19:42

4

The simplest way is to add a new key with the old value, and then delete the old key:

mydict['Make'] = mydict['Label']
del mydict['Label']

answered Feb 11 '19 at 19:42

John Gordon

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score 3 · Answer 3 · answered Feb 11 '19 at 19:42

3

Using pandas

import pandas as pd
df=pd.DataFrame([{'Label': 'Acura', 'Value': '1'}, {'Label': 'Agrale', 'Value': '2'}])
df=df.rename(index=str, columns={"Label": "Make", "Value": "Code"})
df.to_dict('records')

answered Feb 11 '19 at 19:42

mad_

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is pandas really necessary for this? – gold_cy Feb 11 '19 at 19:42
No, but it is easier and should be efficient for more number of columns. Operations like `pop()` are very costly – mad_ Feb 11 '19 at 19:44
sorry but I didn't mention `pop`? – gold_cy Feb 11 '19 at 19:49

How to change dictionary keys in a list of dictionaries?

3 Answers3