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

Posted by nicholasgrzywinski
nicholasgrzywinski
12,830 Points

String Formatting with Dictionaries Challenge

I feel like I should be passing this challenge, when I run this code on my computer it works just fine, the strings variable produces a list of strings formatted by the dicts in values. But every time I press the check work button I get this error: Bummer! string_factory() missing 1 required positional argument: 'template'

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}!"
values = [{"name": "Michelangelo", "food": "PIZZA"}, {"name": "Garlield", "food": "Lasagna"}]

def string_factory(values, template):
    strings = []
    for value in values:
        strings.append(template.format(**value))
    return strings

3 Answers

gyorgyandorka
gyorgyandorka
13,811 Points

Hi Nicholas! I've figured out the problem: you shoudn't give an additional parameter to the function and pass in the template string as an argument - just reach for that pre-defined global variable instead. (Yeah, our function loses its portability if we make it dependent on variables outside its scope, so I totally understand that you automatically declared another parameter - but that's how this challenge works anyway...)

nicholasgrzywinski
nicholasgrzywinski
12,830 Points

Thanks.

Matthew Kelty
Matthew Kelty
2,575 Points
Matthew Kelty
Matthew Kelty
2,575 Points

I used:

def string_factory(values):
    return [template.format(**x) for x in values]
gyorgyandorka
gyorgyandorka
13,811 Points

List comprehension, clever :) (By the way, x could be renamed to value, just as in Nicholas' code, thus following the common pattern of foo-foos when naming an iterable and its items) If the above construct is not familiar for someone, here is Kenny's workshop on comprehensions: https://teamtreehouse.com/library/python-comprehensions-2

Lukáš Miketa
Lukáš Miketa
4,714 Points
Lukáš Miketa
Lukáš Miketa
4,714 Points

Why doesn't template have to be in the paranthesis like this def string_factory(values, template)?

gyorgyandorka
gyorgyandorka
13,811 Points

It could be (and in fact, should), but this challenge - for whatever reason - requires that you use only one parameter, and refer to that pre-defined template variable outside the function.