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Python Python Collections (2016, retired 2019) Dictionaries String Formatting with Dictionaries

Posted by Gregory James
Gregory James
6,537 Points

I already pass this challenge but I am trying to gain a better understanding

How can I unpack this when calling the function? Do I need to twik the function itself? I keep getting a name not defined when i used this format.

string_factory.py 
def favorite_food(dict):
    return "Hi, I'm {name} and I love to eat {food}!".format()

favorite_food(**{name:"Greg",food:"vegan"})

1 Answer

kyle kitlinski
kyle kitlinski
5,619 Points
kyle kitlinski
kyle kitlinski
5,619 Points

Hello Greg, You are close but there are a few issues:

1) Unlike javascript, in python the dictionary keys must be strings favorite_food(**{"name": "Greg", "food": "vegan"})

2) the function takes in a dict, not name and food. So there's 2 ways you can fix this.

a) unpack the dict outside of the function and take in name and food as arguments

def favorite_food(name, food):
    return f"Hi, I'm {name} and I love to eat {food}!"
print(favorite_food(**{"name":"Greg","food":"vegan"}))

b) take in the dict as you are, but unpack it inside the function:

def favorite_food(dict):
    return "Hi, I'm {name} and I love to eat {food}!".format(**dict)
print(favorite_food({"name":"Greg","food":"vegan"}))

I think option B is more of what you're looking for since you're practicing dictionaries though

edit for clarification: In your sample you are spreading the dictionary {"name":"Greg","food":"vegan"} and calling the function. This is effectively the same as 

name = "Greg"
food = "vegan"
favorite_food(name, food)
# this is 2 arguments but you only want 1 dict as an arg
# then with "Hi, I'm {name} and I love to eat {food}!".format() 
# you aren't passing anything to the format function, so the name and food
# aren't defined, so if you unpack the dictionary there, you are passing name and food to the f' string
# "Hi, I'm {name} and I love to eat {food}!".format(**dict)

Hope this helps!