Flatten nested json file

I have the following json file:

{
    "Teams" : ["Dortmund", "Real Madrid"] ,
    "Countries" : [
        "Colombia",
        {
            "Italia" : ["Milan", "Inter", "Juventus"]
        },
        {
            "France" : ["PSG", "Lille"]
        },
        "China"
    ]
}

I want to flatten it in a dictionary, so that it looks like this:

{"Teams": ["Dortmund", "Real Madrid"], "Countries":["Colombia", "Italia", "Milan", "Inter", "Juventus", "France", "PSG", "Lille", "China" ]}

I made this recursive fuction:

def flatten_json(data):
    result = {}
    for key, value in data.items():
        if isinstance(value, dict):
            result.update(flatten_json(value))
        elif isinstance(value, list):
            for i, item in enumerate(value):
                result.update(flatten_json(item))
        else:
            result[key] = value
    return result

But I get this error:

Traceback (most recent call last):
  File "prueba.py", line 46, in <module>
    flattened_dict = flatten_json(organigram)
  File "prueba.py", line 36, in flatten_json
    result.update(flatten_json(item))
  File "prueba.py", line 31, in flatten_json
    for key, value in data.items():
AttributeError: 'str' object has no attribute 'items'

Does anyone know how I can fix it, or how I can achieve the flattening of the json as I want it. Thanks in advance.

>Solution :

You can try:

dct = {
    "Teams": ["Dortmund", "Real Madrid"],
    "Countries": [
        "Colombia",
        {"Italia": ["Milan", "Inter", "Juventus"]},
        {"France": ["PSG", "Lille"]},
        "China",
    ],
}


def flatten(o):
    if isinstance(o, dict):
        for k, v in o.items():
            yield k
            yield from flatten(v)
    elif isinstance(o, list):
        for v in o:
            yield from flatten(v)
    else:
        yield o


out = {k: list(flatten(v)) for k, v in dct.items()}
print(out)

Prints:

{
    "Teams": ["Dortmund", "Real Madrid"],
    "Countries": [
        "Colombia",
        "Italia",
        "Milan",
        "Inter",
        "Juventus",
        "France",
        "PSG",
        "Lille",
        "China",
    ],
}