Python Dictionary: Return First Value in List Or String

Question

I have a list of dictionaries, in which I'm trying to make the value of key 'Username' as the key in a new dictionary, and subsequent key-value pairs as a dictionary value to the 'Username' key in the new dictionary.

One of the checks involves returning the first element from the list if the GECOS value is a list, otherwise return the string value of the GECOS key.

For the first two dictionaries, I'm not able to get the entire string.

I have the data below:

test_list = [
    {
        "Username": "root",
        "UID": "0",
        "GECOS": "root",
        "Group List": [
            ""
        ]
    },
    {
        "Username": "daemon",
        "UID": "1",
        "GECOS": "daemon",
        "Group List": [
            ""
        ]
    },
    {
        "Username": "hplip",
        "UID": "118",
        "GECOS": [
            "HPLIP system user",
            "",
            "",
            ""
        ],
        "Group List": [
            ""
        ]
    },
    {
        "Username": "speech-dispatcher",
        "UID": "111",
        "GECOS": [
            "Speech Dispatcher",
            "",
            "",
            ""
        ],
        "Group List": [
            "pulse",
            "test"
        ]
    }    
]

and the following code:

import json
new_dict = {}
for dict_item in test_list:
    for key in dict_item:
        new_dict[dict_item["Username"]] = {
            'UID'.title().lower(): dict_item['UID'], 
            'GECOS'.title(): dict_item['GECOS'][0] if isinstance(dict_item[key], list) else dict_item['GECOS'],
            'Group List'.title(): [] if all('' == s or s.isspace() for s in dict_item['Group List']) else dict_item['Group List'] 
        }
print(json.dumps(new_dict, indent=4))

The output of this is:

{
    "root": {
        "uid": "0",
        "Gecos": "r",
        "Group List": []
    },
    "daemon": {
        "uid": "1",
        "Gecos": "d",
        "Group List": []
    },
    "hplip": {
        "uid": "118",
        "Gecos": "HPLIP system user",
        "Group List": []
    },
    "speech-dispatcher": {
        "uid": "111",
        "Gecos": "Speech Dispatcher",
        "Group List": [
            "pulse",
            "test"
        ]
    }
}

And the expected output is:

{
    "root": {
        "uid": "0",
        "Gecos": "root",
        "Group List": []
    },
    "daemon": {
        "uid": "1",
        "Gecos": "daemon",
        "Group List": []
    },
    "hplip": {
        "uid": "118",
        "Gecos": "HPLIP system user",
        "Group List": []
    },
    "speech-dispatcher": {
        "uid": "111",
        "Gecos": "Speech Dispatcher",
        "Group List": [
            "pulse",
            "test"
        ]
    }
}

Answer 1

You should not iterate through the keys of each dict. Instead, access the keys directly, as a dict should:

import json
new_dict = {}
for dict_item in test_list:
    new_dict[dict_item["Username"]] = {
        'UID'.title().lower(): dict_item['UID'],
        'GECOS'.title(): dict_item['GECOS'][0] if isinstance(dict_item['GECOS'], list) else dict_item['GECOS'],
        'Group List'.title(): [] if all('' == s or s.isspace() for s in dict_item['Group List']) else dict_item['Group List']
    }
print(json.dumps(new_dict, indent=4))