[Python] pytest throwing module no found in Databricks' notebook

I'm recreating below test scenario but constantly getting below error:

https://learn.microsoft.com/en-us/azure/databricks/notebooks/testing

ImportError while importing test module '/Workspace/python_tests/dummy_test.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/lib/python3.12/importlib/__init__.py:90: in import_module
return _bootstrap._gcd_import(name[level:], package, level)
E ModuleNotFoundError: No module named 'dummy_test'
=========================== short test summary info ============================
ERROR dummy_test.py
!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!
=============================== 1 error in 0.45s ===============================


This is the structure of my /Workspace/python_tests directory and each file:

1. dummy.py

import pyspark
from pyspark.sql import SparkSession
from pyspark.sql.functions import col

# Because this file is not a Databricks notebook, you
# must create a Spark session. Databricks notebooks
# create a Spark session for you by default.
spark = SparkSession.builder.appName('integrity-tests').getOrCreate()

def dummy():
return "I am a dummy"

1. dummy_test.py

# import pytest
import pyspark
from dummy import *


def test_dummy():
assert dummy() == "I am a dummy"

1. pyTestRunner (notebook)

%pip install pytest

import pytest
import sys

# Skip writing pyc files on a readonly filesystem.
sys.dont_write_bytecode = True

# Run pytest.
retcode = pytest.main([".", "-v", "-p", "no:cacheprovider"])

# Fail the cell execution if there are any test failures.
assert retcode == 0, "The pytest invocation failed. See the log for details."

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