Day 173

[vaskoz]

Good morning! Here's your coding interview problem for today.

This problem was asked by Stripe.

Write a function to flatten a nested dictionary. Namespace the keys with a period.

For example, given the following dictionary:

{
    "key": 3,
    "foo": {
        "a": 5,
        "bar": {
            "baz": 8
        }
    }
}

it should become:

{
    "key": 3,
    "foo.a": 5,
    "foo.bar.baz": 8
}