Even numbers using list comprehensions

Write a function that receives a list of numbers and returns only the even elements. You must use List comprehensions to solve it.

even_numbers([5, 4, 3, 2, 1]) == [4, 2]
import unittest


class EvenNumberTestCase(unittest.TestCase):
    def test_multiple_even_numbers(self):
        self.assertEqual(even_numbers([5, 4, 3, 2, 1]), [4, 2])

    def test_one_even_numbers(self):
        self.assertEqual(even_numbers([5, 4, 3, 7, 9, 1]), [4])

    def test_no_even_numbers(self):
        self.assertEqual(even_numbers([5, 3, 7, 9, 1]), [])

    def test_empty_list_even_numbers(self):
        self.assertEqual(even_numbers([]), [])