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Python

Posted by Hasan Ahmad
Hasan Ahmad
6,727 Points

String formatting, unpacking dicts

Can someone help me, i dont know what is going wrong here.

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

def string_factory(args):
    new_list = []
    for item in args:
        new_list.append(template.format(**item))
    return new_list



string_fact = string_factory({'name': 'hasan', 'food': 'kebabs'})
print(string_fact)

2 Answers

Steven Parker
Steven Parker
243,186 Points
Steven Parker
Steven Parker
243,186 Points

The function requires a list of dictionaries as an argument, but you're calling it with a single dictionary as the argument.

But more importantly, the challenge only asks you to create the function. You don't need to call it yourself or print anything.

Hasan Ahmad
Hasan Ahmad
6,727 Points

I already done and completed the challenge at the start of the year. I just came back to revise and test the code on my machine. It gave me this error:

Traceback (most recent call last):
  File "/Users/Hasan/PycharmProjects/beginner_projects/tests.py", line 11, in <module>
    string_fact = string_factory({'name': 'hasan', 'food': 'kebabs'})
  File "/Users/Hasan/PycharmProjects/beginner_projects/tests.py", line 6, in string_factory
    new_list.append(template.format(**item))
TypeError: format() argument after ** must be a mapping, not str
Steven Parker
Steven Parker
243,186 Points
Steven Parker
Steven Parker
243,186 Points

That's right, because by passing it a single dictionary, your loop is iterating through keys (str) from the dictionary instead of dictionaries (mapping) from a list.

But it will work if you call it like this instead:

string_fact = string_factory([{'name': 'hasan', 'food': 'kebabs'}])
Hasan Ahmad
Hasan Ahmad
6,727 Points
Hasan Ahmad
Hasan Ahmad
6,727 Points

It still does not work, now i get this:

Traceback (most recent call last):
  File "/Users/Hasan/PycharmProjects/beginner_projects/tests.py", line 11, in <module>
    string_fact = string_factory([{'name': 'hasan', 'food': 'kebabs'}])
  File "/Users/Hasan/PycharmProjects/beginner_projects/tests.py", line 6, in string_factory
    new_list.append(template.format(**item))
IndexError: tuple index out of range