There seems to be a problem with the python version. The expected solution often doesn't even have all the letters in the triplets.

Example:

triplets = [
['w', 'f', 'x'],
['i', 'm', 'l'],
['a', 'f', 's'],
['g', 'p', 'f'],
['o', 'b', 'x'],
['r', 's', 'u'],
['c', 'n', 'h']
]

Is somehow expected to result in 'kleqpiufzh'.

Several letters are missing from the result.