Update list items inside a list (matrix)

Question

I'm trying to update all list items that are inside a list. Better to say it's a matrix. I'm building it like that: grids = [["#"] * grid_size for _ in range(grid_size)]

Output if my grid for a size 4:

[['#', '#', '#', '#'],
 ['#', '#', '#', '#'],
 ['#', '#', '#', '#'],
 ['#', '#', '#', '#']]

Next to that I have a list of dictionaries with several words inside. Code: all_words = [x for x in words]

Output of all words:

...
...
 {'definition': 'Maladie virale caractérisée par une éruption de vésicules '
                'disposées sur le trajet des nerfs sensitifs.',
  'word': 'ZONA',
  'word_length': Decimal('4')},
 {'definition': "Partie d'une surface sphérique comprise entre deux plans "
                'parallèles.',
  'word': 'ZONE',
  'word_length': Decimal('4')},
 {'definition': 'Musique de danse très rythmée, originaire de la Martinique.',
  'word': 'ZOUK',
  'word_length': Decimal('4')},
 {'definition': 'Naïf, niais.', 'word': 'ZOZO', 'word_length': Decimal('4')}]

What I would like to do is to replace the "#" in the matrix in order to add the 'word' that are in my dictionaries. Here for the example 'ZONA', 'ZONE', 'ZOUK' and 'ZOZO' that are my four last words.

Desired output:

[['Z', 'O', 'N', 'A'],
 ['Z', 'O', 'N', 'E'],
 ['Z', 'O', 'U', 'K'],
 ['Z', 'O', 'Z', 'O']]

The best would be of course to add only these four words so that the matrix doesn't expand more than it is. I tried with a list comprehension inside another list comprehension but I'm messing everything up...

Thanks a lot for your help ! Btv-

Answer 1

I think this is what you have right now

all_words = [ {'definition': 'Maladie virale caracterisee par une eruption de vesicules '
    ...:                 'disposees sur le trajet des nerfs sensitifs.',
    ...:   'word': 'ZONA',
    ...:   'word_length': Decimal('4')},
    ...:  {'definition': "Partie d'une surface spherique comprise entre deux plans "
    ...:                 'paralleles.',
    ...:   'word': 'ZONE',
    ...:   'word_length': Decimal('4')},
    ...:  {'definition': 'Musique de danse tres rythmee, originaire de la Martinique.',
    ...:   'word': 'ZOUK',
    ...:   'word_length': Decimal('4')},
    ...:  {'definition': 'Naif, niais.', 'word': 'ZOZO', 'word_length': Decimal('4')}]

First get a list of only the words with the correct length

only_words = [word["word"] for word in all_words if len(word["word"]) == 4]

Then use list() to make the word into a list of individual letters

[list(word) for word in only_words[:4]]

[['Z', 'O', 'N', 'A'],
 ['Z', 'O', 'N', 'E'],
 ['Z', 'O', 'U', 'K'],
 ['Z', 'O', 'Z', 'O']]

Edit: I have added an if statement into the first list comp to filter words by their length. I see you have a "word_length" key but I'm unfamiliar with the Decimal() thing.

In the second list comp i have used list slicing to take the first n words only