Discriminability tests really slow, circle ci timeout

[sampan501]

My issue is about ...

Reproducing code example:

Sample code to reproduce the problem

Error message

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  ...

Version information

• OS: [e.g. macOS]
• Python Version [e.g. 3.7.3]
• Package Version [e.g. 0.0.1]