Issue with itertools.product that not list as expected

Question

Python itertools.product module not working as expect when I'm extracting string "[1,2], [3,4], [5,6,7], [8,9]" from a json object here:

},
 "combos_matrix": "[1,2], [3,4], [5,6,7], [8,9]"
},

But it's working when I put directly numbers in ():

list(itertools.product([1,2], [3,4], [5,6,7], [8,9]))

Here is my results when I extract data from json and try the function

Json sample:

},
"combos_matrix": "[1,2], [3,4], [5,6,7], [8,9]"
},

Code by using json object:

combos_matrix = map_json["world"]["combos_matrix"]
print(combos_matrix)
combos_list = list(itertools.product(combos_matrix))
print(combos_list)

Output:

[1,2], [3,4], [5,6,7], [8,9]
[('[',), ('1',), (',',), ('2',), (']',), (',',), (' ',), ('[',), ('3',), (',',), ('4',), (']',), (',',), (' ',), ('[',), ('5',), (',',), ('6',), (',',), ('7',), (']',), (',',), (' ',), ('[',), ('8',), (',',), ('9',), (']',)]

What I'm expecting and this is the result when I give the function directly the list of numbers:

Code:

combos_list = list(itertools.product([1,2], [3,4], [5,6,7], [8,9]))
print(combos_list)

Output:

[(1, 3, 5, 8), (1, 3, 5, 9), (1, 3, 6, 8), (1, 3, 6, 9), (1, 3, 7, 8), (1, 3, 7, 9), (1, 4, 5, 8), (1, 4, 5, 9), (1, 4, 6, 8), (1, 4, 6, 9), (1, 4, 7, 8), (1, 4, 7, 9), (2, 3, 5, 8), (2, 3, 5, 9), (2, 3, 6, 8), (2, 3, 6, 9), (2, 3, 7, 8), (2, 3, 7, 9), (2, 4, 5, 8), (2, 4, 5, 9), (2, 4, 6, 8), (2, 4, 6, 9), (2, 4, 7, 8), (2, 4, 7, 9)]

Can you help on this guy, I guess I'm missing something.

Answer 1

Extracting combos_matrix from JSON objects makes it a string representation of the list, but you need the actual list, you can get it from json.loads():

combos_matrix = map_json["world"]["combos_matrix"]
print(combos_matrix)

combos_matrix_json = f'[{combos_matrix}]'

combos_list = json.loads(combos_matrix_json)

combos_result = list(itertools.product(*combos_list))
print(combos_result)

Output:

[1,2], [3,4], [5,6,7], [8,9]
[(1, 3, 5, 8), (1, 3, 5, 9), (1, 3, 6, 8), (1, 3, 6, 9), (1, 3, 7, 8), (1, 3, 7, 9), (1, 4, 5, 8), (1, 4, 5, 9), (1, 4, 6, 8), (1, 4, 6, 9), (1, 4, 7, 8), (1, 4, 7, 9), (2, 3, 5, 8), (2, 3, 5, 9), (2, 3, 6, 8), (2, 3, 6, 9), (2, 3, 7, 8), (2, 3, 7, 9), (2, 4, 5, 8), (2, 4, 5, 9), (2, 4, 6, 8), (2, 4, 6, 9), (2, 4, 7, 8), (2, 4, 7, 9)]

Answer 2

The type of the dictionary value is string, so you need to convert this string to a list first (NOTE: your string is missing the initial [ and final ], so when converting this string to a list it needs to be added).

For string->list conversion you can use ast.literal_eval:

from ast import literal_eval
from itertools import product

dct = {"combos_matrix": "[1,2], [3,4], [5,6,7], [8,9]"}

lst = literal_eval(f"[{dct['combos_matrix']}]")
for p in product(*lst):
    print(p)

Prints:

(1, 3, 5, 8)
(1, 3, 5, 9)
(1, 3, 6, 8)
(1, 3, 6, 9)
(1, 3, 7, 8)
(1, 3, 7, 9)
(1, 4, 5, 8)
(1, 4, 5, 9)
(1, 4, 6, 8)
(1, 4, 6, 9)
(1, 4, 7, 8)
(1, 4, 7, 9)
(2, 3, 5, 8)
(2, 3, 5, 9)
(2, 3, 6, 8)
(2, 3, 6, 9)
(2, 3, 7, 8)
(2, 3, 7, 9)
(2, 4, 5, 8)
(2, 4, 5, 9)
(2, 4, 6, 8)
(2, 4, 6, 9)
(2, 4, 7, 8)
(2, 4, 7, 9)