[BUG] AttributeError: 'list' object has no attribute 'add_vertices'

[sighingnow]

Describe the bug

A longstanding issue that usually happens when vineyard run out of memory and failed to add new vertices / edges to the fragment.

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Cell In [27], line 1
----> 1 g = load_ogbn_mag(sess)

File /opt/gs-for-build/python/graphscope/dataset/ogbn_mag.py:79, in load_ogbn_mag(sess, prefix)
     75     sess = get_default_session()
     77 graph = sess.g()
     78 graph = (
---> 79     graph.add_vertices(os.path.join(prefix, "paper.csv"), "paper")
     80     .add_vertices(os.path.join(prefix, "author.csv"), "author")
     81     .add_vertices(os.path.join(prefix, "institution.csv"), "institution")
     82     .add_vertices(os.path.join(prefix, "field_of_study.csv"), "field_of_study")
     83     .add_edges(
     84         os.path.join(prefix, "author_affiliated_with_institution.csv"),
     85         "affiliated",
     86         src_label="author",
     87         dst_label="institution",
     88     )
     89     .add_edges(
     90         os.path.join(prefix, "paper_has_topic_field_of_study.csv"),
     91         "hasTopic",
     92         src_label="paper",
     93         dst_label="field_of_study",
     94     )
     95     .add_edges(
     96         os.path.join(prefix, "paper_cites_paper.csv"),
     97         "cites",
     98         src_label="paper",
     99         dst_label="paper",
    100     )
    101     .add_edges(
    102         os.path.join(prefix, "author_writes_paper.csv"),
    103         "writes",
    104         src_label="author",
    105         dst_label="paper",
    106     )
    107 )
    109 return graph

AttributeError: 'list' object has no attribute 'add_vertices'

Additional context
Add any other context about the problem here.

[sighingnow]

Working on that.