add link to possibly running python code in the browser.

Not going to do that for now, as framework to import the
python code I want into it might be a bit difficult..

NOTES.md

@@ -24,6 +24,8 @@ uses afterSetExtremes event on xAxis to load data, which then set's it via setDa
 Stacked area chart:
 https://web.archive.org/web/20200109053708/https://www.highcharts.com/demo/area-stacked
 
+Running Python code in browser:
+https://github.com/brython-dev/brython
 
 Graphs
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