def METHOD_NAME(request, usage_id, submission_uuid):
    """
    Attempt to claim a submission lock for grading.
    Returns:
    - lockStatus (string) - One of ['not-locked', 'locked', 'in-progress']
    """
    handler_name = "delete_submission_lock"
    body = {"submission_uuid": submission_uuid}
    # Return raw response to preserve HTTP status codes for failure states
    response = call_xblock_json_handler(request, usage_id, handler_name, body)
    # Lock contested returns a 403
    if response.status_code == 403:
        raise LockContestedError()
    # Other errors should raise a blanket exception
    if response.status_code != 200:
        raise XBlockInternalError(context={"handler": handler_name})
    return json.loads(response.content)