What is a mapping? etc.

Question

Since it's asking for a new list of strings I made an empty list titled new_list.

I made the function title string_factory that accepts the argument with the name list_of_dicts.

The list of dicts (including keys and values) is names values (which was already created).

I thought I should then take each item within that list and append it to the new_list which is empty.

After that, I can return the new_list with each item appended.

It says append() argument after ** must be a mapping, not a list. I really don't understand what I'm doing when it comes to dictionaries and packing/unpacking

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}!"

new_list = []

def string_factory(list_of_dicts):
    for items in values:
        new_list.append(**values)
    return new_list

Answer 1 · 2017-03-03T18:51:04Z

March 3, 2017 6:51pm

a mapping is a dictionary, so it throws that error because you have a list of dicts after the asterisks. you are pretty close, you just need to tweak a few things. i got this to work without adding any lines of code. firstly, list_of_dicts is your parameter, so that's what you use inside of the function body, not values. values is the argument you pass in when calling the function. secondly, you are not using the template in the function. that is what you append to new_list, while calling the format method on template. to fill in the blanks of the template, you call your loop variable, items, with the keyword args (two asterisks) as the argument to the format method.

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Joshua Dam

Joshua Dam

What is a mapping? etc.

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james south

james south