UnicodeDecodeError when importing vispy

[Andrea Cogliati]

I'm getting the following error while importing vispy subpackages, such as vispy.scene:

(gdocm4d) PS C:\Users\Andrea Cogliati\Documents\LighTopTech\4D-Qt5-Gui> python .\vptest.py

Traceback (most recent call last):

  File ".\vptest.py", line 1, in <module>

    from vispy import scene

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\scene\__init__.py", line 33, in <module>

    from .visuals import *  # noqa

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\scene\visuals.py", line 18, in <module>

    from .. import visuals

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\visuals\__init__.py", line 14, in <module>

    from .axis import AxisVisual  # noqa

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\visuals\axis.py", line 11, in <module>

    from .visual import CompoundVisual

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\visuals\visual.py", line 90, in <module>

    from .. import gloo

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\gloo\__init__.py", line 47, in <module>

    from . import gl  # noqa

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\gloo\gl\__init__.py", line 34, in <module>

    from ._constants import *  # noqa

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\site-packages\vispy\gloo\gl\_constants.py", line 326, in <module>

    if repr(ob).startswith('GL_'):

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\_sitebuiltins.py", line 61, in __repr__

    self.__setup()

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\_sitebuiltins.py", line 51, in __setup

    data = fp.read()

  File "C:\Users\Andrea Cogliati\anaconda3\envs\gdocm4d\lib\encodings\cp1252.py", line 23, in decode

    return codecs.charmap_decode(input,self.errors,decoding_table)[0]

UnicodeDecodeError: 'charmap' codec can't decode byte 0x9d in position 188: character maps to <undefined>

The problem only started to occur recently, and I'm not sure what I may have changed to cause it to happen. Any suggestions?