Ask HN: A flexible python based cms

Hi, I would like to know if there is a flexible cms where i can define my own content type.

It would typically be title Image description level date tags

For a given tag, the cms should generate a page with all custom objects that have the tag automatically (or with minimal manual intervention). The objects should be sortable on the relevant fields.

I should also have the option of writing some content and including some of the objects, in which case, the objects should be auto-formatted based on some predefined template. Is there any cms that can do this with some minimal customizations or is it better to roll my own based on django/flask?

Thank you.