text: """Tests for the binary exercise
  
  Implementation note:
  If the argument to parse_binary isn't a valid binary number the
  function should raise a ValueError with a meaningful error message.
  """
  import unittest
  
  from binary import parse_binary
  
  
  class BinaryTest(unittest.TestCase):
      def test_binary_1_is_decimal_1(self):
          self.assertEqual(parse_binary("1"), 1)
  
      def test_binary_10_is_decimal_2(self):
          self.assertEqual(parse_binary("10"), 2)
  
      def test_binary_11_is_decimal_3(self):
          self.assertEqual(parse_binary("11"), 3)
  
      def test_binary_100_is_decimal_4(self):
          self.assertEqual(parse_binary("100"), 4)
  
      def test_binary_1001_is_decimal_9(self):
          self.assertEqual(parse_binary("1001"), 9)
  
      def test_binary_11010_is_decimal_26(self):
          self.assertEqual(parse_binary("11010"), 26)
  
      def test_binary_10001101000_is_decimal_1128(self):
          self.assertEqual(parse_binary("10001101000"), 1128)
  
      def test_invalid_binary_text_only(self):
          with self.assertRaisesWithMessage(ValueError):
              parse_binary("carrot")
  
      def test_invalid_binary_number_not_base2(self):
          with self.assertRaisesWithMessage(ValueError):
              parse_binary("102011")
  
      def test_invalid_binary_numbers_with_text(self):
          with self.assertRaisesWithMessage(ValueError):
              parse_binary("10nope")
  
      def test_invalid_binary_text_with_numbers(self):
          with self.assertRaisesWithMessage(ValueError):
              parse_binary("nope10")
  
      # Utility functions
      def setUp(self):
          try:
              self.assertRaisesRegex
          except AttributeError:
              self.assertRaisesRegex = self.assertRaisesRegexp
  
      def assertRaisesWithMessage(self, exception):
          return self.assertRaisesRegex(exception, r".+")
  
  
  if __name__ == '__main__':
      unittest.main()
  