Question

I have some problem with my function.

I do an SQL Query to obtain a list that have some dictionary with only a key/value element.
This is a sample of my output:

myDictList = [{'id': 55, 'sigla': 'SNG'}, {'id': 62, 'sigla': 'TRP'}, 
 {'id': 71, 'sigla': 'PCNIM'},  {'id': 72, 'sigla': 'pc2ni'}, 
 {'id': 73, 'sigla': 'ccas'}, {'id': 74, 'sigla': 'ased1'}, 
 {'id': 75, 'sigla': '131s'}, {'id': 76, 'sigla': 'r888'}, 
 {'id': 56, 'sigla': 'DBL'}]

The id are unique (for SQL constraint).

I’ve build a list of id in that way

r_id_list = list(rid['id'] for rid in roomList)

Now, i would build a dict. like that from myDictList:

{55:'SNG',62:'TRP',71:'PCNIM'.... and so on}

More over, i want to avoid part of code like that:

finalDict = {}
for element in myDictList:
    finalDict.update({element['id']:element['sigla']})

I want to do that for some reasons:

• I don’t want to do two separate query to obtain some data that i can retrive with one
• I don’t want to iterate to every list element for retrive sigla value from r_id_list element

Some suggestion for a compact code that will not include a for cycle inside a for cycle, and increase the complexity?

Answer 1

finalDict = dict([(k['id'], k['sigla']) for k in myDictList])

EDIT1
As comment mentioned, it will be a better way to do.

finalDict = dict(((k['id'], k['sigla']) for k in myDictList))

EDIT2

finalDict = dict((k['id'], k['sigla']) for k in myDictList)