[MacPorts] #60137: `sudo port -f clean --all all` fails

[MacPorts]

#60137: `sudo port -f clean --all all` fails
-------------------------+--------------------
 Reporter:  AndyWharton  |      Owner:  (none)
     Type:  defect       |     Status:  new
 Priority:  Normal       |  Milestone:
Component:  base         |    Version:  2.6.2
 Keywords:               |       Port:
-------------------------+--------------------
 `sudo port -f clean --all all` fails, below are the last few lines of the
 output:

 {{{
     --->  Cleaning py38-zope-proxy
     --->  Cleaning py38-zopeinterface
     --->  Cleaning pybind11
     Error:

     You must select a Python variant; you cannot select -python38 alone.

     Error: Unable to open port: Invalid variant selection.
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/60137>
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