If you have an existing site, you may want to switch to using update Paragraphs on existing fields. You can utilize a custom module with an update hook to do this and then update your database through the UI or with "Drush updatedb". The follow is a sample of one. The things that you'll need to change are:

The Migrate Extras module, provides the MigrateDestinationEntityAPI so you can specify a custom entity as a destination.

The Group module for Drupal 7 is based around the Entity API. Individual groups have a "Group Type" in the module, which is an Entity. Since it's an Entity, it has fields.

It also has specific permissions and roles, which apply to any Group of this Group type.

After enabling the module and creating some domains go to Administration > People > Permissions (http://example.com/admin/people/permissions) to configure the module permissions.

A Flickr JSON parser for the Feeds extensible parsers module.

Example how to set up a Flickr feed to grab a single user's images

Besides this module enable the sub-module Feeds UI (feeds_ui, part of Feeds) and its dependencies.

The behaviour of linking to internal entities (e.g. nodes) could be much improved with the integration of the "Linkit"-module.