Takes a list of dicts each of which has an '@id' key,
    sorts the elements in the list by the value of the @id key.
    Assumes that @id is unique or the dicts have a meaningul < operator

def _inplace_sort_by_id(unsorted_list):
    """Takes a list of dicts each of which has an '@id' key,
    sorts the elements in the list by the value of the @id key.
    Assumes that @id is unique or the dicts have a meaningul < operator
    """
    if not isinstance(unsorted_list, list):
        return
    sorted_list = [(i.get('@id'), i) for i in unsorted_list]
    sorted_list.sort()
    del unsorted_list[:]
    unsorted_list.extend([i[1] for i in sorted_list])