Flat nested dicts.

flatten.py

def flatten(dct: dict, , prefix="", glue: str = "__") -> dict:
    flat = {}
    prefix = f"{prefix}{glue}" if prefix else ""

    def _flat(dct):
        _dct = {}
        for k, v in dct.items():
            if not isinstance(v, list) and not isinstance(v, dict):
                _dct[k] = v

            elif isinstance(v, dict):
                for kd, vd in v.items():
                    _dct[kd] = vd

        return _dct

    if not isinstance(dct, list) and not isinstance(dct, dict):
        return dct

    if isinstance(dct, list):
        idx = 0
        for child in dct:
            _key = f"{prefix}{idx}"
            flat[_key] = flatten(child, _key)
            idx += 1

    if isinstance(dct, dict):
        for key, value in dct.items():
            _key = f"{prefix}{key}"
            flat[_key] = flatten(value, _key)

    flat = _flat(flat)
    return flat