[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 someuser12):

 After upgrading py36-matplotlib under Mac OS 10.11.6 and Mac OS 10.13.6,
 and after a fresh install of py37-matplotlib and of py37-matplotlib
 +tkinter (thus without Cairo) under a fresh install of Macports under Mac
 OS 10.15.3, I see a similar problem: "import matplotlib" fails under all
 of these installations of Matplotlib, with the same error message `Symbol
 not found: _MPL_matplotlib__image_ARRAY_API`.

 In the case of py37-matplotlib +tkinter in the fresh install under Mac OS
 10.15.3, the complete message is
 {{{
 >>> import matplotlib.pyplot
 Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
   File
 "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7
 /site-packages/matplotlib/__init__.py", line 205, in <module>
     _check_versions()
   File
 "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7
 /site-packages/matplotlib/__init__.py", line 190, in _check_versions
     from . import ft2font
 ImportError:
 dlopen(/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7
 /site-packages/matplotlib/ft2font.cpython-37m-darwin.so, 2): Symbol not
 found: _MPL_matplotlib__contour_ARRAY_API
   Referenced from:
 /opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7
 /site-packages/matplotlib/ft2font.cpython-37m-darwin.so
   Expected in: flat namespace
  in
 /opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7
 /site-packages/matplotlib/ft2font.cpython-37m-darwin.so
 >>>
 }}}

 It is not clear to me if this linkage issue is related to this ticket.
 Should I open a new ticket?

 So far, I found no workaround (reinstalling py36-matplotlib @3.1.2 instead
 of the newest 3.1.3 does not solve the problem, which is presumably due to
 the upgrade of some other package). Numpy and Scipy, in contrast, still
 work.

-- 
Ticket URL: <https://trac.macports.org/ticket/60074#comment:11>
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