Sample Initial test for my idea for a type safety function decorator for Python

test_type_safety.py

import unittest

from type_safety import typed


class TypeSafetyTestCase(unittest.TestCase):
    def test_positional_typing(self):
        """
        When the @typed() decorator is used with a list of types
        it should force these types on the corresponding positional
        arguments of the function.
        """
        # decorate a sample function
        @typed('basestring', 'int', 'basestring')
        def greet(name, age, country)
            return ('Hello, my name is {0}. I am {1} years old '
                    'and I live in {2}').format(name, age, country)
    
        # test once with correctly typed arguments
        self.assertEqual(greet('Hamisch', 12, 'Germany'),
                         ('Hello, my name is Hamisch. I am 12 years old '
                          'and I live in Germany'))
        
        with self.assertRaises(TypeError):
            greet(34, 23, 'Switzerland')
        with self.assertRaises(TypeError):
            greet('Paul', 23, 34924.4234)
        with self.assertRaises(TypeError):
            greet('Paul', '45', 'Australasia')
    
    def test_keyword_typing(self):
        """
        When the @typed() decorator is used with a list of types
        by keyword it should force these types on the corresponding
        keyword arguments of the function.
        """
        # decorate a sample function
        @typed(me='basestring', problem='basestring', reason='basestring')
        def apologise(me, problem, reason):
            return 'I, {0} am sorry for the {1} casued by {2}'.format(me, problem, reason)