Could anyone explain String formatting with dictionaries challenge step-by-step?

Question

I've tried a variety of things ranging from following the example in the video to going through many questions about the same challenge asked by other students and answers from other students or mods. 
Not sure what I'm missing or just not understanding. I'd really appreciate some help on the matter. After 2 hours of attempts, I think it's time to ask for help.
```string_factory.py
Original code below
def favorite_food(dict):
    return "Hi, I'm {name} and I love to eat {food}!".format()
Code used in the video previous to this challenge
def unpacker(firstname=None, lastname=None):
    if firstname and lastname:
        print("Hi {} {}!".format(firstname, lastname))
    else:
        print("Hi, no name!")
unpacker(**{"lastname": "Wick", "firstname": "John"})
```

csr13 · Accepted Answer

Whenever you use " ".format() you can unpack  a dict  by using **, so you need to unpack (not manually)
the dict to the format() function.
If you were to unpack the dict manually you would do this:
python
def favorite_food(dict):
    food = dict['food']
    name = dict['name']
    return "Hi, I'm {} and I love to eat {}!".format(name, food)

But you can also use ** to your benefit to allocate the keys in their reserved placeholders without unpacking a dict manually.
By using ** I think what happens is you are unpacking the dict and passing it as keyword arguments that fit the reserved placeholder, but at the same time creating those named parameters.
This:
python
def favorite_food(dict):
    return "Hi, I'm {name} and I love to eat {food}!".format(**dict)

Is the same as this:
python
def favorite_food(dict):
    return "Hi, I'm {name} and I love to eat {food}!".format(name='yourname', food='yourfood')

If the dict passed to the funcion is like this.
python
dict_passed_to_function = {'name': 'yourname', 'food': 'yourfood' }

Hope this helps :dizzy:

Welcome to the Treehouse Community

Looking to learn something new?

Erik Burmeister

Erik Burmeister

Could anyone explain String formatting with dictionaries challenge step-by-step?

1 Answer

csr13

csr13

Erik Burmeister

Erik Burmeister