Rearrange introduction of Setuptools and move to debugtoolbar.

Replace [testing] with [dev].
Make narrative text more descriptive of what is going on with `extras_require`

1 files changed, 8 insertions, 2 deletions

diff --git a/docs/quick_tutorial/debugtoolbar.rst b/docs/quick_tutorial/debugtoolbar.rst
index 907f3e0b6..2607c83f2 100644
--- a/docs/quick_tutorial/debugtoolbar.rst
+++ b/docs/quick_tutorial/debugtoolbar.rst
@@ -38,7 +38,7 @@ Steps
 
         cd ..; cp -r ini debugtoolbar; cd debugtoolbar
 
-#.  Add ``pyramid_debugtoolbar`` to our project's dependencies in ``setup.py``:
+#.  Add ``pyramid_debugtoolbar`` to our project's dependencies in ``setup.py`` as a :term:`Setuptools` "extra" for development:
 
     .. literalinclude:: debugtoolbar/setup.py
         :language: python
@@ -46,10 +46,11 @@ Steps
         :emphasize-lines: 10-16, 20-22
 
 #.  Install our project and its newly added dependency.
+    Note that we use the extra specifier ``[dev]`` to install development requirements and surround it and the period with double quote marks.
 
     .. code-block:: bash
 
-        $VENV/bin/pip install -e .
+        $VENV/bin/pip install -e ".[dev]"
 
 #.  Our ``debugtoolbar/development.ini`` gets a configuration entry for ``pyramid.includes``:
 
@@ -96,6 +97,11 @@ experience otherwise inexplicable client-side weirdness, you can shut it off
 by commenting out the ``pyramid_debugtoolbar`` line in ``pyramid.includes``
 temporarily.
 
+Finally we've introduced the concept of :term:`Setuptools` extras.
+These are optional or recommended features that may be installed with an "extras" specifier, in this case, ``dev``.
+The specifier is the name of a key in a Python dictionary, and is surrounded by square brackets when invoked on the command line, for example, .
+The value for the key is a Python list of dependencies.
+
 .. seealso:: See also :ref:`pyramid_debugtoolbar <toolbar:overview>`.