python-311 fails to install

[steve%prd.co.uk@localhost (Steve Blinkhorn)]

amd64-9.2

I am trying to install the most recent firefox.  There is a problem
with python-311 which seems top be a recurrent stumbling-block:

pkg_add: Package `python311-3.11.7' conflicts with `py311-cElementTree-[0-9]*',
and `py311-cElementTree-3.11.5' is installed.
pkg_add: Package `python311-3.11.7' conflicts with `py311-expat-[0-9]*', and `py
311-expat-3.11.5nb1' is installed.
pkg_add: Can't install dependency python311>=3.11.6nb1
pkg_add: Expected dependency python311>=3.11.6nb1 still missing pkg_add: 1 package addition failed

How to resolve this?

-- 
Steve Blinkhorn <steve%prd.co.uk@localhost>