flatten.py

import json


def flatten(o):
    """Flatten dicts and lists, recursively, JSON-style

    It's a generator that yields key-value pairs.

    Example:
        >>> dict(flatten({"a": [{"b": 1}, [2, 3], 4, {"c.d": 5, True: 6}]}))
        {'.a[0].b': 1,
         '.a[1][0]': 2,
         '.a[1][1]': 3,
         '.a[2]': 4},
         '.a[3]["c.d"]': 5,
         '.a[3][true]': 6}
    """
    if isinstance(o, dict):
        for key, value in o.items():
            if isinstance(key, str) and "." in key:
                key = '["{}"]'.format(key)
            elif isinstance(key, str):
                key = ".{}".format(key)
            else:
                key = '[{}]'.format(json.dumps(key))
            for subkey, subvalue in flatten(value):
                yield key + subkey, subvalue
    elif isinstance(o, list):
        for index, value in enumerate(o):
            for subkey, subvalue in flatten(value):
                yield "[{}]".format(index) + subkey, subvalue
    else:
        yield "", o