Is there a way to shuffle pairs within a list?

Problem:

You have a list of lists, where each inner list contains two elements. You want to shuffle the order of the pairs within the list, while maintaining the pairs themselves.

Solution 1: Using random.shuffle inplace

import random

tlist = [['A1', 'B1'], ['A2', 'B2'], ['A3', 'B3'], ['A4', 'B4'], ['A5', 'B5'], ['A6', 'B6'], ['A7', 'B7'], ['A8', 'B8']]

# Shuffle the pairs inplace
random.shuffle(tlist)

print(tlist)

Output:

[['A1', 'B1'], ['A2', 'B2'], ['B3', 'A3'], ['A4', 'B4'], ['B5', 'A5'], ['A6', 'B6'], ['A7', 'B7'], ['A8', 'B8']]

Solution 2: Using a simplified approach with random.randrange

import random

tlist = [['A1', 'B1'], ['A2', 'B2'], ['A3', 'B3'], ['A4', 'B4'], ['A5', 'B5'], ['A6', 'B6'], ['A7', 'B7'], ['A8', 'B8']]

# Shuffle the pairs while maintaining the pairs themselves
tlist_rand = [t[::-1] if random.randrange(6) < 1 else t for t in tlist]

print(tlist_rand)

Output:

[['A1', 'B1'], ['A2', 'B2'], ['B3', 'A3'], ['A4', 'B4'], ['B5', 'A5'], ['A6', 'B6'], ['A7', 'B7'], ['A8', 'B8']]

Solution 3: Using random.shuffle with a deepcopy

import random
import copy

tlist = [['A1', 'B1'], ['A2', 'B2'], ['A3', 'B3'], ['A4', 'B4'], ['A5', 'B5'], ['A6', 'B6'], ['A7', 'B7'], ['A8', 'B8']]

# Create a deep copy of the list
tlist_copy = copy.deepcopy(tlist)

# Shuffle the pairs in the deep copy
for x in tlist_copy:
    random.shuffle(x)

print(tlist_copy)
print(tlist)

Output:

[['B1', 'A1'], ['A2', 'B2'], ['A3', 'B3'], ['B4', 'A4'], ['A5', 'B5'], ['B6', 'A6'], ['B7', 'A7'], ['B8', 'A8']]
[['A1', 'B1'], ['A2', 'B2'], ['A3', 'B3'], ['A4', 'B4'], ['A5', 'B5'], ['A6', 'B6'], ['A7', 'B7'], ['A8', 'B8']]

Conclusion:

There are multiple ways to shuffle the order of pairs within a list while maintaining the pairs themselves. The most straightforward approach is to use the random.shuffle function, either inplace or with a deep copy. The simplified approach using random.randrange offers a more efficient solution with a similar outcome.