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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def authenticate_credentials(self, userid, password):
 """ Authenticate the userid and password against username and password. """

        credentials = {
            get_user_model().USERNAME_FIELD: userid,
            'password': password
        }
        user = authenticate(**credentials)

        if user is None:
            raise exceptions.AuthenticationFailed(_('Invalid username/password.'))

        if not user.is_active:
            raise exceptions.AuthenticationFailed(_('User inactive or deleted.'))

        return (user, None)