[MacPorts] #60486: py-emcee: Add py38-emcee subport

[MacPorts]

#60486: py-emcee: Add py38-emcee subport
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  Reporter:  lpagani91  |      Owner:  lpsinger
      Type:  request    |     Status:  closed
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.6.2
Resolution:  fixed      |   Keywords:
      Port:  py-emcee   |
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Comment (by reneeotten):

 it would also be good to update the port to its latest version. I know
 there are some (breaking) changes between versions 2 and 3). I would
 recommend updating the {{{py-emcee}}} port to version three (i.e., follow
 upstream) and if you need it to keep version two as {{{py-emcee2}}} and
 make both ports conflict.

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Ticket URL: <https://trac.macports.org/ticket/60486#comment:4>
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