I found this seed pod and would like to grow them. What are they?
If not that, then you might consider comparing to the tree peony.
https://www.gardeningknowhow.com/ornamental/flowers/peony/how-to-grow-a-tree-peony.htm
I'm not getting a good look at the individual seeds, but a possibility is blackberry lily, which is not a true lily, but is in the iris family. This website has seedpod images that may help. Also, you can take it to a local nursery who might recognize it offhand.
http://theseedsite.co.uk/db1.html
https://plants.ces.ncsu.edu/plants/iris-domestica/