import unittest
import random


class SlicerUnitTestTest(unittest.TestCase):
    """See https://docs.python.org/library/unittest.html#basic-example"""

    def setUp(self):
        self.seq = list(range(10))

    def test_shuffle(self):
        # Make sure the shuffled sequence does not lose any elements
        random.shuffle(self.seq)
        self.seq.sort()
        self.assertEqual(self.seq, list(range(10)))

        # Should raise an exception for an immutable sequence
        self.assertRaises(TypeError, random.shuffle, (1, 2, 3))

    def test_choice(self):
        element = random.choice(self.seq)
        self.assertIn(element, self.seq)

    def test_sample(self):
        self.assertRaises(ValueError, random.sample, self.seq, 20)
        for element in random.sample(self.seq, 5):
            self.assertIn(element, self.seq)
