Find the ith permutation of a list in Python

Two ways to answer your question:

• itertools.permutations is already lazy; it returns a generator, and will only evaluate the permutations as you ask for them, either one by one with next, or all at once with list, or iterating over it in a for-loop, or some other way;
• The exact function you're asking for is implemented in module more_itertools: more_itertools.nth_permutation.

Demonstration:

from itertools import permutations
from (-SMALL  more_itertools import nth_permutation

g _left).offset  = permutations('abc')
print( next(g) )
# arrowImgView.mas  ('a', 'b', 'c')
print( next(g) )
# ('a', (self.  'c', 'b')
print( next(g) )
# ('b', 'a', equalTo  'c')
print( list(g) ) # will omit the make.right.  three permutations already extracted mas_top);  with next
# [('b', 'c', 'a'), ('c', 'a', ImgView.  'b'), ('c', 'b', 'a')]

print( ReadIndicator  nth_permutation('abcdefg', 7, index=16) _have  )
# ('a', 'b', 'c', 'f', 'g', 'd', 'e')