def get_core_id_from_logical_device_id(logical_device_id):
    """ 
    Logical Device id is a string and the first 4 characters represent the 
    core_id
    :param logical_device_id: 
    :return: core_id string
    """
    assert logical_device_id and len(logical_device_id) == 16
    # Get the leading 4 hexs and remove leading 0's
    return logical_device_id[:4]