even_elements.py

import unittest


def even_elements(l):
    """
    Given a list, this function returns a new list
    with the with items found in the even indexes only
    """
    if len(l) == 0:
        return l

    n = len(l)//2
    results = []
    for i in range(n):
        results.append(l[i*2])

    return results


class TestEvenElements(unittest.TestCase):

    def test_empty(self):
        self.assertEqual(even_elements([]), [])

    def test_one(self):
        self.assertEqual(even_elements([0]), [])

    def test_two(self):
        self.assertEqual(even_elements([0, 1]), [0])

    def test_seven(self):
        self.assertEqual(even_elements([0, 1, 2, 3, 4, 5, 6]), [0, 2, 4])

    def test_ten(self):
        self.assertEqual(even_elements([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]),
                        [0, 2, 4, 6, 8])

if __name__ == '__main__':
    unittest.main()