Installing swh.model does not install its dependencies

After installing swh.model, running

>$ swh-identify

shows error -

Traceback (most recent call last):
  File "/home/hrishi/.local/bin/swh-identify", line 5, in <module>
    from swh.model.cli import identify
  File "/home/hrishi/.local/lib/python3.8/site-packages/swh/model/cli.py", line 14, in <module>
    from swh.core.cli import swh as swh_cli_group
ModuleNotFoundError: No module named 'swh.core'

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Migrated from T3220 (view on Phabricator)