Would like to ask for some advice/ available libraries that can be use to check dependencies between functions. Function test_isupper() will need to check if test_upper()function is successfully run. Else, not going to run test_isupper()
import unittest
class TestStringMethods(unittest.TestCase):
    def test_upper(self):
        self.assertEqual('foo'.upper(), 'FOO')
    def test_isupper(self):
        self.assertTrue('FOO'.isupper())
        self.assertFalse('Foo'.isupper())