The DjDT "handle" isn't visible on the polls application as the templates
are missing <body> tags for brevity.
Backport of 72b7aecbbfbec0ceb1a829eef82a68d7283df604 from main.
Added a tutorial step that highlights Django Debug Toolbar, on of the
most common third party packages. It also added a mention of
djangopackages.com as a place to search for other libraries and a
link to Adam Johnson’s post on evaluating whether a package is
well-maintained.
Third-party packages are one of Django’s strengths. This should give
folks a sound route in.
