Summary

• The unittest module is a framework for developing reliable automated tests.
• You define test cases by subclassing from unittest.TestCase.
• The unittest.main() function is useful for running all of the
  tests in a module.
• The setUp() and tearDown() fixtures are used to run code before and after each test method.
• Test methods are defined by creating method names that start with test_ on test case objects.
• The various TestCase.assert... methods can be used to make a test method fail when the right conditions aren't met.
• Use TestCase.assertRaises() in a with-statement to check that the right exceptions are thrown in a test.

1. Test-driven development, or simply TDD, is a form of software development where tests are written first, That is, before you write the actual functionality to be tested. This may seem backwards at first, but it can be a surprisingly powerful technique...