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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def prompt_user_passwd(self, host, realm):
 """Override this in a GUI environment!"""

        import getpass
        try:
            user = input("Enter username for %s at %s: " % (realm, host))
            passwd = getpass.getpass("Enter password for %s in %s at %s: " %
                (user, realm, host))
            return user, passwd
        except KeyboardInterrupt:
            print()
            return None, None