Continuing numbering from heading to list in toctree

Question

I'm looking to get list numbers to continue on from heading numbers. I've tried the :numbered: directive in .. toctree:, but that only produces numbers for the headings.

For example:

Section
=====

Sub Section
-----------

#. item 1
#. item 2

  #. item 3

Which would generate:

1. Section

1.1 Sub Section

1.1.1 Item 1

1.1.2 Item 2

1.1.2.1 Item 3

What (if any) would be the approach to producing this result?