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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 get_users(self, email):
 """ Make sure users are staff users. Additionally to the other PasswordResetForm conditions ensure that the user is a staff user before sending them a password reset email. :param email: Textual email address. :return: List of users. """

        # Django 1.8 supports this feature.
        if hasattr(super(PasswordResetForm, self), 'get_users'):
            return (
                u for u in super(PasswordResetForm, self).get_users(email)
                if u.is_staff and u.is_active
            )

        # Django Django < 1.8 support we can do this manually.
        active_users = get_user_model()._default_manager.filter(email__iexact=email, is_active=True)
        return (u for u in active_users if u.has_usable_password() and u.is_staff and u.is_active)