Dummy Visual Python module

Intended to allow automated testing of Visual Python codes.
Uses a logging handler and replacement classes for the VPython interface

Incomplete, work in progress 

Contents
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visual.py     The replacement for VPython to be imported by test code
color.py      Replacement for VPython's visual.color (very incomplete)

test.py       An example code being checked
runtest.py    Checks the test.py code, prints some diagnostics

handler.py    Custom logging handler to record events