Pycharm: MultipleInstanceError: Multiple incompatible subclass instances of PyDevTerminalInteractiveShell are being created

Question

In PyCharm, if I run a script in debug mode (with debug console on), then stop at a breakpoint, and try to type something into the console, I get:

MultipleInstanceError: Multiple incompatible subclass instances of PyDevTerminalInteractiveShell are being created.

Does anybody know what might be causing this and how to fix it?

Answer 1

For me, I had this issue when using ipdb in another terminal from the same code. I had ipdb present in file A, and a terminal with an ipython shell open running this code. I commented out the ipdb bits from file A and ran the debugger in pycharm and this error started up. When I closed the shell I had open in my terminal the error went away.