@Burhanudin Badiuzaman​ :

The error message suggests that there may be a circular import happening within the databricks_test_helper module, which is preventing the Test class from being properly imported.

One possible solution is to import the Test class directly from the databricks_test_helper.test_helper

module, instead of using a wildcard import from the top-level databricks_test_helper module. Here is an example of how to modify your code:

from databricks_test_helper.test_helper import Test
 
expected = set([(s, 'double') for s in ('AP', 'AT', 'PE', 'RH', 'V')])
 
Test.assertEquals(expected, set(powerPlantDF.dtypes), "Incorrect schema for powerPlantDF")

This should allow you to import the Test class without triggering the circular import issue.

Alternatively, you could try updating the databricks_test_helper package to a newer version, as this may have already fixed the circular import issue. You can do this by running pip install --upgrade databricks_test_helper.

I hope this helps! Let me know if you have any further questions.