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Python

Posted by Tony Brackins
Tony Brackins
28,766 Points

format() argument after ** must be a mapping, not list

Create a function named string_factory that accepts a list of dictionaries and a string. Return a new list build by using .format() on the string, filled in by each of the dictionaries in the list.

Here's my code: Please help!

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):
  strings = []
  for items in dicts:
   string.format(**dicts) 
  return strings

print(string_factory(dicts, string))

6 Answers

Juan Martin
Juan Martin
14,335 Points
Juan Martin
Juan Martin
14,335 Points

Hello my friend!

Here you can see 2 possible ways of doing it:

First:

def string_factory(dictionary, strings):
  string_list = []
  for i in range(len(dictionary)):
    string_list.append(strings.format(**dictionary[i]))

  return string_list

Second:

def string_factory(dictionary, strings):
  string_list = []
  for element in dictionary:
    string_list.append(strings.format(**element))

  return string_list

Hope this helps!

Have an awesome night :)

Spencer Johnson
Spencer Johnson
19,708 Points
Spencer Johnson
Spencer Johnson
19,708 Points

this worked for me:

def string_factory(dicts, string):
  formatted = []
  for data in dicts:
    new_dict = data
    formatted.append(string.format(**new_dict))
  return formatted


print(string_factory(dicts, string))
Maxim Andreev
Maxim Andreev
24,529 Points
Maxim Andreev
Maxim Andreev
24,529 Points

Can someone dumb down '**' please, I understand how to use **kwargs, and *args for functions but how is the double asterick being used in this case?

beven nyamande
beven nyamande
9,575 Points
beven nyamande
beven nyamande
9,575 Points

double asterisks are for unpacking items in a dictionary

yanni jain
yanni jain
693 Points
yanni jain
yanni jain
693 Points

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(str,dict): new_list= [ string.format(dicts[0]), string.format(dicts[1]), string.format(dicts[2]), string.format(dicts[3]) ]

return new_list

i dont know where i am wrong it is giving an iteration error in ( new_list=[ )

yanni jain
yanni jain
693 Points

please reply and correct me!!

Daniel Muchiri
Daniel Muchiri
15,407 Points
Daniel Muchiri
Daniel Muchiri
15,407 Points

This worked for me:

def string_factory(dicts, string):
    string_list = []
    for a_dict in dicts:
        string_list.append(string.format(**a_dict))

    return string_list