[Python] How to unit test nested exception in python?

I have the scenario as follows,

class SomeException(Exception):
pass

class SomeOtherException(Exception):
pass

def first_fn():
raise SomeException

def second_fn():
try:
first_fn()
except Exception as e:
raise SomeOtherException from e


I want to check that, somewhere in the chain whether "SomeException" was raised. I have written the unittest as follows,

import unittest

class MyTestCase(unittest.TestCase):

def test_case(self):
self.assertRaises(SomeException, second_fn)

if __name__ == '__main__':
unittest.main()


But the unit test fails. But if I do the following,

class MyTestCase(unittest.TestCase):

def test_case(self):
self.assertRaises(SomeOtherException, second_fn)



then it is passing.

Is there a way to check whether a particular nested exception was raised in the exception stack trace?

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