如何在Python中從字符串中的特定位置（而不是索引）中刪除字符

Question

所以我有這個代碼：

def myprogram():
import string
import random
import getpass

inputpasswd = getpass.getpass("Password: ")
passwd = ("I<3StackOverflow")
if passwd == inputpasswd:
    qwerty = input("Type something: ")
    def add_str(lst):
        _letters = ("1","2","3","4","5","6","7","8","9","0","q","w","e","r","t","z","u","i","o","p","a","s","d","f","g","h","j","k","l","y","x","c","v","b","n","m","!","#","$","%","&","/","(",")","=","?","*","+","_","-",";"," ")
        return [''.join(random.sample(set(_letters), 1)) + letter + ''.join(random.sample(set(_letters), 1))for letter in lst]

    print(''.join(add_str(qwerty)))
    input("")
else:
    print("Wrong password")
    input("")

我的問題是：我如何制作一個相反的程序，所以它接受了一堆垃圾字母並將其轉換為有意義的文本？

示例：如果我在此程序中鍵入類似“aaaaaaa”的內容，則會將其轉換為“mapma＆”at7ar8a2ga-ka *“

在這個新程序中，我想輸入“mapma＆”at7ar8a2ga-ka *“並輸出”aaaaaaa“。

Answer 1

這對你有用嗎？：

s="1a23a45a6"
print(s[1::3]) # aaa

Answer 2

這樣做： initial_str = random_str[1:-1:3] ，其中random_str是帶垃圾的字符串