REL: v3.3.1

This is the first bugfix release of the 3.3.x series.

This release contains several critical bug-fixes:

• fix docstring import issues when running Python with optimization
• fix hist with categorical data, such as with Pandas
• fix install on BSD systems
• fix nbagg compatibility with Chrome 84+
• fix ordering of scatter marker size in 3D plots
• fix performance regression when plotting Paths
• fix reading from URL in imread
• fix several regressions with new date epoch handling
• fix some bad constrained and tight layout interactions with colorbars
• fix use of customized toolbars in TkAgg and WXAgg backends