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Python Python Collections (Retired) Dictionaries String Formatting with Dictionaries

Brent Liang
PLUS
Brent Liang
Courses Plus Student 2,944 Points
Posted by Brent Liang
Brent Liang
Courses Plus Student 2,944 Points

Trouble with expected output

The question asks for returning a new list built by using .format() of all the dicts in the list onto the given string.

The error message is that "didn't get all expected output". I tried in workspace but couldn't check my output so unable to determine which values are lacking.

What's wrong?

strings.py 
dicts = [
    {'name': 'Michelangelo',
     'food': 'PIZZA'},
    {'name': 'Garfield',
     'food': 'lasanga'},
    {'name': 'Walter',
     'food': 'pancakes'},
    {'name': 'Galactus',
     'food': 'worlds'}
]

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

def string_factory (dicts, string):
    new_list = []
    for item in dicts:
        string.format(**item)
        new_list.extend(string)
    return new_list

1 Answer

Evan Demaris
Evan Demaris
64,262 Points

Hi Brent,

The extend method adds a list or iterable to a list. If you provide an iterable to it, then it treats that iterable as a list.

In this case, Python is iterating through your string and adding each letter to your list, instead of adding the string to your list. You can simplify the entire function as follows;

def string_factory(dicts, string):
    return [string.format(**item) for item in dicts]

Hope that helps!