Printing combinations of two lists in Python

You dont need these many loops for this. Just use combinations and product from itertoools

>>> from itertools import combinations, product
>>> 
>>> v1 = [1, 2]
>>> v2 = ["a","b"]
>>> 
>>> all_v1 = [e for i in range(len(v1)) for e in combinations(v1,i+1)]
>>> all_v2 = [e for i in range(len(v1)) for e in combinations(v2,i+1)]
>>> 
>>> for i, (x,y) in enumerate(product(all_v2, all_v1)):
...     print (f'com{i} <-{x} with {y}')
... 
com0 <-('a',) with (1,)
com1 <-('a',) with (2,)
com2 <-('a',) with (1, 2)
com3 <-('b',) with (1,)
com4 <-('b',) with (2,)
com5 <-('b',) with (1, 2)
com6 <-('a', 'b') with (1,)
com7 <-('a', 'b') with (2,)
com8 <-('a', 'b') with (1, 2)

The product() from itertools results in the Cartesian product of the two lists. By using this function you avoid all the loops:

import itertools

v1 = [1, 2]
v2 = ["a","b"]
combinations = list(itertools.product(v1, v2))
>> [(1, "a"), (1, "b"), (2, "a"), (2, "b")]