entities – How to use “conent entity” type in a View?

I have used the “content entity example” coming from the example project.

This example module/:

  • defines a “Contact” entity; it can have extra fields, displays can be configured (web/admin/structure/content_entity_example_contact_settings),
  • gives the user the form to add content (contact info) to it. (/web/content_entity_example_contact/add)
  • shows a list of the contacts (/web/content_entity_example_contact/list)

I want to make my list as a View, but this content entity type “Contact” is not there to select it. (I see only the node content types, users, taxonomy etcI

How can I use this content in a View ? What do I have to do to make this content available in the Views UI ? Where can I find the content entity types to create a view ? Or how can I add those ?