Python中递归函数的解释

Question

我是 Python 的新手，并试图将我的头放在递归函数上。我理解整体概念，但我遇到了一个我似乎无法完全理解它在做什么的例子。对正在发生的事情进行逐步细分将是理想的，请提前感谢您的帮助。def anagrams(s):    if s == '':            return [s]    else:        ans = []        for w in anagrams(s[1:]):             for pos in range(len(w)+1):                ans.append(w[:pos] + s[0] + w[pos:])    return ans  

Answer 1

def anagrams(s):

    # if argument <s> is a blank String

    if s == '':

        # return a list is just <s> in it

        return [s]

    else:

        # create a List

        ans = []

        # for each String character in calling this function recursively,

        # but removing character 0!

        for w in anagrams(s[1:]): 

            # for character position number starting at 0 and ending at

            # the length of the returned value of the recursed function

            # plus 1

            for pos in range(len(w)+1):

                # append a string with the following concatenation:

                # - the returned value's string from position 0 to position <pos>

                # - the character at position 0 of <s>

                # - the returned value's string from position <pos> to the end

                ans.append(w[:pos] + s[0] + w[pos:])

    # return the list

    return ans