问题描述:
Write a function to print all permutations of a given string including duplicates.

测试用例:
["assert permute_string('ab')==['ab', 'ba']", "assert permute_string('abc')==['abc', 'bac', 'bca', 'acb', 'cab', 'cba']", "assert permute_string('abcd')==['abcd', 'bacd', 'bcad', 'bcda', 'acbd', 'cabd', 'cbad', 'cbda', 'acdb', 'cadb', 'cdab', 'cdba', 'abdc', 'badc', 'bdac', 'bdca', 'adbc', 'dabc', 'dbac', 'dbca', 'adcb', 'dacb', 'dcab', 'dcba']"]

生成的代码:
from itertools import permutations

def permute_string(s):
    return [''.join(p) for p in permutations(s)]