Hello: 

The attached python file runs a pdb interactive session for a generator. It produces an error in Python 3.7 Beta 3, but no error in 3.6.

I searched for this issue and there do seem to be things that are related to it already, but I haven't investigated the cause of this issue and am not acquainted with the details of the pdb module, so I was unable to determine whether previous reports discuss this same problem.