prepare test data for shown form model

[tai271828]

With this pull request #87 , we have not only shown form created, but also using the model to manipulate the DB. However, we are still lack of the testing for the model and the corresponding CRUD. The first step would be creating the testing data.

Describe the solution you'd like
Refer to commit 196863b . We have created data for ohshown events.

Additional context
https://docs.djangoproject.com/en/3.2/topics/migrations/

You should rarely, if ever, need to edit migration files by hand, but it’s entirely possible to write them manually if you need to. Some of the more complex operations are not autodetectable and are only available via a hand-written migration, so don’t be scared about editing them if you have to.