why preprocess pubs in this way?

[CodeW1zard]

it seems that the each publication is converted to featues for multiple times in similiar ways? what is meaning of that? thanks!
`
def extract_author_features(item, order=None):

title_features, keywords_features, venue_features = extract_common_features(item)

author_features = []

for i, author in enumerate(item["authors"]):

    if order is not None and i != order:

        continue

    name_feature = []

    org_features = []

    org_name = string_utils.clean_name(author.get("org", ""))

    if len(org_name) > 2:

        org_features.extend(transform_feature(org_name, "org"))

    for j, coauthor in enumerate(item["authors"]):

        if i == j:

            continue

        coauthor_name = coauthor.get("name", "")

        coauthor_org = string_utils.clean_name(coauthor.get("org", ""))

        if len(coauthor_name) > 2:

            name_feature.extend(

                transform_feature([string_utils.clean_name(coauthor_name)], "name")

            )

        if len(coauthor_org) > 2:

            org_features.extend(

                transform_feature(string_utils.clean_sentence(coauthor_org.lower()), "org")

            )

    author_features.append(

        name_feature + org_features + title_features + keywords_features + venue_features

    )

author_features = list(chain.from_iterable(author_features))

return author_features

`