How to call a variable within a function if it runs under a Class

Question

How to call a variable within a function:

What is the Right approach:

• Should define the variable before class or
• We can define it under the class or function

Sample Code:

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import time

timeStamp = time.strftime("%Y%m%d%H%M%S")  # <-- Is this right Approach
class Scanner:

    INFO = 0
    DEBUG = 3
    timeStamp = time.strftime("%Y%m%d%H%M%S") # <-- ?

    def __init__(self, config_file, verbose=False):
        """ Constructor """

    def ask_passwords(self):
    def ldap_init(self):
    def hosts_module_scanner(self):
    def users_module_scanner(self):
    def ldap_reporting(self, user_list):
            self.write_report(failed_users, "users_ldap_report-{}.txt".format(timeStamp))


def option_parser(prog_version):
if __name__ == '__main__':
    scanner.ask_passwords()
    scanner.ldap_init()
    scanner.hosts_module_scanner()
    scanner.users_module_scanner()

Note: In the above example it doesn't work if i define under class.