Python kodundaki hata nedir?

import datetime,os
from re import fullmatch
from typing import NoReturn
class user:
    def __init__(self,username,joinDate,email,password):
        self.username=username
        self.joinDate=joinDate
        self.email=email
        self.password=password
    username=None
    joinDate=None
    email=None
    password=None
    def takeDatas(self,mode=str):
        self.email=str(input("Email: "))
        self.username=str(input("Username: "))
        self.password=str(input("Password: "))
        if(mode=="show"):
            return print(f"Username: {self.username}\nEmail: {self.email}\nPassword: {self.password}\nJoin date: {datetime.datetime.now}")
        if(mode=="hide"):
            pass
    def showDatas(self):
            print(f"Username: {self.username}\nEmail: {self.email}\nJoin date: {self.joinDate}\n")
            input()
    def changePassword(self):
        self.password=str(input("New Password: "))
    def checkEmail(email):
        characters = r'\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z|a-z]{2,}\b'
        if(fullmatch(characters,email)):
            print("Succesfully created.")
        else:
            print("Email is invalid.")
    def verifyUser():
        if(user[y].username!=None and user[y].email!=None and user[y].username!=None and user[y].joinDate!=None):
            __email__=str(input("Email: "))
            __password__=str(input("Password: "))
            if(user[y].email==__email__ and user[y].password==__password__):
                print("Datas valid.")
                return "1"
            elif(user[y].email==__email__ and user[y].password!=__password__):
                print("Invalid password.")
                return "2"
            else:
                print("Invalid datas.")
                return "0"
        else:
            print("User not found.")
            return "-1"
x=0
y=int
z=1
while(z!=0):
    action=str(input("Create user: 1\nLogin: 2\nShow Datas: 3\nChange password: 4\nExit: 0\n\nAction: "))
    if(action=="1"):
        user[x]=user      
        user[x].takeDatas("hide")
        user[x].checkEmail()
        x=y
        x+=1
    elif(action=="2"):        #hata çıkabilir buraya bak ve try except komutu yaz.
        if(user[y].username!=None and user[y].email!=None and user[y].username!=None and user[y].joinDate!=None):
            user[y].verifyUser()
    elif(action=="3"):
        if(user[y].verifyUser()=="1"):
            user[y].showDatas
        else:
            pass
    elif(action=="4"):
        if(user[y].verifyUser()=="1"):
            user[y].changePassword
        else:
            pass
    elif(action=="0"):
        z=0
    else:
        print("Invalid action.")
        input()
        continue