Plugin allows to define accordion, each item might have another items.
Choose a site you want to install the add-on to from the dashboard. Then go to Apps -> Install app and click Install next to Accordion app.
Redeploy the site.
Run pip install -e git+git://github.com/aldryn/aldryn-accordion.git#egg=aldryn_accordion.
Add below apps to INSTALLED_APPS:
INSTALLED_APPS = [
…
'aldryn_accordion',
…
]