I have two nested dictionaries and I want to merge them into one (where second dict overrides first dict values). I saw a lot of beautiful solutions for merging "flat" (not nested) dictionaries, e.g.:

```
dict_result = dict1.copy()
dict_result.update(dict2)

```

or

```
dict_result = dict(dict1.items() + dict2.items())

```

or (my favorit one)

```
dict_result = dict(d1,**d2)

```

but couldn't find the most efficient way to merge multi-nested dicts.

I'm trying to avoid recursion. What is your proposition?