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

Asif Choudhury
Asif Choudhury
2,086 Points
Posted by Asif Choudhury
Asif Choudhury
2,086 Points

How to iterate over a LIST of dictionaries? I know how to iterate over items in a dictionary though.

I know how to iterate items in a dictionary in a for loop:

for k,v in dixonary.items(): print(k,v) But I am struggling to figure out the way to iterate a list of dictionary.

Please help.

string_factory.py 
# Example:
# values = [{"name": "Michelangelo", "food": "PIZZA"}, {"name": "Garfield", "food": "lasagna"}]
# string_factory(values)
# ["Hi, I'm Michelangelo and I love to eat PIZZA!", "Hi, I'm Garfield and I love to eat lasagna!"]

template = "Hi, I'm {name} and I love to eat {food}!"

1 Answer

Mike Wagner
Mike Wagner
23,559 Points
Mike Wagner
Mike Wagner
23,559 Points

Surprisingly enough, it's not all that different to iterate over a list of dictionaries.

for dict_entity in dict_list:

will handle each individual dictionary in the list of dictionaries just as if they were individual items in a list or any other iterable. The slightly more thought involved portion is what to do with those dictionaries as we handle them. The challenge wants to use the **kwarg functionality to unpack the values from each dictionary into the template string using the keywords in the placeholders. Here is a pretty good write-up on args and kwargs in Python that might help you understand what we're expected to do in the challenge a little better.

In our above for-loop we establish where we're sourcing the keywords from to match the string template dict_entity so we give that to our format operation like so 

template.format(**dict_entity)

this will result in a string that matches expectation for one of the dictionaries. Since the challenge expects us to return a list of all the strings this function will generate, we'll have to set up a list at the beginning of the function. Then we would append this freshly formatted string into the list (since it wasn't asking for any particular order). After we've run the for-loop to completion, we'll have a list full of neatly formatted strings 

["Hi, I'm Michelangelo and I love to eat PIZZA!", "Hi, I'm Garfield and I love to eat lasagna!"]

which we'll return at the end of the function. I didn't want to do it all for you, and since you said you knew how to iterate over a dictionary, I assume you'll be able to work the final product out on your own. If you run into any issues, I can flesh this out a bit more to provide a more.. example-filled answer. Good luck!