add trypython.jcubic.pl (EbookFoundation#6628)

* add trypython.jcubic.pl

* Update more/free-programming-playgrounds.md

Co-authored-by: ImVector <[email protected]>

Co-authored-by: ImVector <[email protected]>

Author: jcubic

more/free-programming-playgrounds.md

@@ -220,6 +220,7 @@
 * [Python.org Shell](https://www.python.org/shell)
 * [Repl.it - NiceDualPoint](https://repl.it/repls/NiceDualPoint#main.py)
 * [SoloLearn](https://code.sololearn.com/python)
+* [Try Python](https://trypython.jcubic.pl) - Jakub T. Jankiewicz
 
 
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