wx.svg fails to work starting from wxpython 4.2.4. Specifically, any call to SVGimage.RenderToGC would fail.

The cause of this issue is the switch from cython 3.0 to 3.1. In cython 3.0 enums values were defined at the module level. But starting in cython 3.1 they are only defined in the enum namespace.

Therefore, wx.svg._nanosvg.SVG_FLAGS_VISIBLE was accessible in wxpython 4.2.3, but now we need to use wx.svg._nanosvg.SVGflags.SVG_FLAGS_VISIBLE.