[MacPorts] #60074: py37-matplotlib @3.1.3_0+cairo+webagg: importing fails

[MacPorts]

#60074: py37-matplotlib @3.1.3_0+cairo+webagg: importing fails
----------------------------+------------------------
  Reporter:  ladavid        |      Owner:  reneeotten
      Type:  defect         |     Status:  assigned
  Priority:  Normal         |  Milestone:
 Component:  ports          |    Version:  2.6.2
Resolution:                 |   Keywords:  catalina
      Port:  py-matplotlib  |
----------------------------+------------------------

Comment (by reneeotten):

 thank you Frank for checking that! So it seems the issue is with the
 {{{cairo}}} backend and, again, I don't see this on Mojave which makes
 troubleshooting difficult for me because I have no way of reproducing it.
 Having said that, can you please provide the output of {{{port -v
 installed py37-cairo cairo}}}, jus to make sure you have the default
 variants as well? In my case this gives:
 {{{
 > port -v installed py37-cairo cairo
 The following ports are currently installed:
   cairo @1.16.0_0+quartz+x11 (active) platform='darwin 18' archs='x86_64'
 date='2019-10-01T20:17:19-0400'
   py37-cairo @1.19.0_0 (active) platform='darwin 18' archs='x86_64'
 date='2020-01-28T09:56:43-0500'
 }}}

 Secondly, please do {{{sudo port -dv test py37-cairo}}}; that test-suite
 runs without trouble on my machine let's see if that's the case for you as
 well.

-- 
Ticket URL: <https://trac.macports.org/ticket/60074#comment:6>
MacPorts <https://www.macports.org/>
Ports system for macOS