przykład na facebook

flashcards = [
    {
        "id": 1,
        "pytanie": "cokolwiek",
        "back_side": {
            "answer": "NIe wiem",
            "code": ""
        }
    },
    {
        "id": 2,
        "pytanie": "ahahahha",
        "back_side": {
            "answer": "NIe wiem",
            "code": ""
        }
    },
    {
        "id": 3,
        "pytanie": "lblblbbl",
        "back_side": {
            "answer": "sdkfjsdkjfskd",
            "code": ""
        }
    },
]

packages = [
    {"first_packages": [1, 3]},
    {"second_packages": [2, 3]},
]

def get_packages():
    all_packages = list()

    for pack in packages:
        for key, values in pack.items():
            # tworzenie nowego pakietu - np. {"first_packages": []}
            data = {key: []}
            for number in values:
                for card in flashcards:
                    if card['id'] == number:
                        data[key].append(card)
            all_packages.append(data)

    return all_packages

get_packages()

#-----------------------------------------------------------------------------------

Wynik

[{'first_packages': [{'back_side': {'answer': 'NIe wiem', 'code': ''},
                      'id': 1,
                      'pytanie': 'cokolwiek'},
                     {'back_side': {'answer': 'sdkfjsdkjfskd', 'code': ''},
                      'id': 3,
                      'pytanie': 'lblblbbl'}]},
 {'second_packages': [{'back_side': {'answer': 'NIe wiem', 'code': ''},
                       'id': 2,
                       'pytanie': 'ahahahha'},
                      {'back_side': {'answer': 'sdkfjsdkjfskd', 'code': ''},
                       'id': 3,
                       'pytanie': 'lblblbbl'}]}]