I'm building a custom form for one of my content types. I want to be able to import some of the existing fields and save out the node programmatically. On drupal 7 I always used the field_attach_form function to do this for me. It looks like that function has been removed in Drupal 8. Can anyone give me some pointers on how I can do the same thing and include fields from a content type in my custom form? I've scoured the internet looking for this all day, any help would be appreciated. Thanks