Get permutations of a string

get_permutations.py

def get_permutations(input_str):
	if len(input_str) <= 1:
		return set([input_str])

	all_chars_except_last = input_str[:-1]
	last_char = input_str[-1:]

	permutations_of_all_chars_except_last = get_permutations(all_chars_except_last)

	permutations = set()
	for perm_str in permutations_of_all_chars_except_last:
		for position in range(len(all_chars_except_last) + 1):
			item = (
				perm_str[:position] + last_char + perm_str[position:]
			)
			permutations.add(item)

	return permutations