Matplotlib v3.3.1 missing matplotlib._png which breaks yt

[biboyd]

Bug report

Bug summary
Upgrading to matplotlib v3.3.1 breaks yt. When you try to import yt you get and Error saying matplotlib._png cannot be imported.

import yt

Actual outcome

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/__init__.py", line 63, in <module>
    from yt.fields.api import \
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/fields/api.py", line 19, in <module>
    from . import angular_momentum
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/fields/angular_momentum.py", line 26, in <module>
    from .vector_operations import \
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/fields/vector_operations.py", line 32, in <module>
    from yt.geometry.geometry_handler import \
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/geometry/geometry_handler.py", line 29, in <module>
    from yt.utilities.parallel_tools.parallel_analysis_interface import \
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/utilities/parallel_tools/parallel_analysis_interface.py", line 30, in <module>
    from yt.data_objects.image_array import ImageArray
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/data_objects/image_array.py", line 18, in <module>
    from yt.visualization.image_writer import write_bitmap, write_image
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/visualization/image_writer.py", line 29, in <module>
    import yt.utilities.png_writer as pw
  File "/home/bb/anaconda3/lib/python3.7/site-packages/yt/utilities/png_writer.py", line 13, in <module>
    import matplotlib._png as _png
ModuleNotFoundError: No module named 'matplotlib._png'

Expected outcome

no errors

Version Information

• Operating System: Ubuntu 18.04

• Python Version: 3.7.7

• yt version: 3.6 and 3.6.dev0 (Tested stable and development versions). installed both via conda

• Other Libraries (if applicable): matplotlib v3.3.1

[welcome]

Hi, and welcome to yt! Thanks for opening your first issue. We have an issue template that helps us to gather relevant information to help diagnosing and fixing the issue.

[neutrinoceros]

Hi ! this issue was already reported when mpl 3.3.0 came out #2752
and was addressed on our master branch !

[matthewturk]

We're working to get a bugfix release out -- hopefully *very* soon -- onto the various conda channels.

…

On Fri, Aug 21, 2020 at 4:21 PM Clément Robert ***@***.***> wrote: Closed #2887 <#2887>. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2887 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAVXO3LGW6FBJ6FXDVG6WDSB3QLZANCNFSM4QHVCWHA> .

[neutrinoceros]

Yes sorry I should have mentioned that :)

[biboyd]

Okay thanks! Ya, I missed that issue when I did a quick search.

[neutrinoceros]

No problem ! have a good day :-)