itertools – Paarbildung aus zwei Listen

import itertools

a = [1,2]
b = ['a','b','c']

pairs = list(itertools.product(a, b))
list_of_pairs = [f"{item[0]}{item[1]}" for item in pairs ]

print(pairs)
print(list_of_pairs)
[(1, 'a'), (1, 'b'), (1, 'c'), (2, 'a'), (2, 'b'), (2, 'c')]
['1a', '1b', '1c', '2a', '2b', '2c']