Thonny supports CircuitPython and will display the REPL and it will save files to devices. It also supports several MicroPython variants in addition to standard Python (CPython).
I tried this version of Thonny on my Windows 10 machine (hint: use the thonny…exe file). I used pip install thonny in a command window as I have Python 3.7 installed and that worked great, installing the program and creating a desktop icon.
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