How to set repo branch restriction for kind = force

[Gourav Garg]

I am unable to set "Allow rewriting branch history" using bitbucket API. I pass this as json_data to my request

def modify_branch_restrictions(self, repo_slug, workspace_id, br_id, json_data):
    """ Modify branch restrictions by adding single user to it in specified repository
    :param br_id: branch restriction id
    :param json_data: json object for modification
    :return JSON object containing modified branch restriction data
    """
    url = self.BITBUCKET_API_URL + workspace_id + '/' + repo_slug + '/branch-restrictions/' + br_id
    headers = {'Content-Type': 'application/json', 'Authorization': 'Bearer ' + self.access_token}

    print('url', url)
    res = requests.put(url, headers=headers, data=json_data)
    if res.status_code == 401:
        self.refresh_token()
        return self.modify_branch_restrictions(repo_slug, workspace_id, br_id, json_data)
    elif res.status_code == 200:
        return res.json()
    else:
        logging.log(level=logging.ERROR, msg=str(res.status_code) + res.text)
        return None

br_json = json.dumps({'kind': val['kind'], 'users': user_ids, 'groups': val['groups']})
res = BB_API.modify_branch_restrictions(repo_slug, workspace, str(val['id']), br_json)

ERROR:root:400{"type": "error", "error": {"message": "kind force requires users and groups to be empty, null, or omitted"}}

But if I pass users and groups as empty or drop them then there is no error and the condition remains unchecked.