In [3]:

    

def get_earliest(date1, date2):
    # Tuple unpacking
    m1, d1, y1 = date1.split("/")
    m2, d2, y2 = date2.split("/")
    
    # Comparing tuples
    return date1 if (y1, m1, d1) < (y2, m2, d2) else date2


    

In [4]:

    

import unittest


class GetEarliestTests(unittest.TestCase):

    """Tests for get_earliest."""

    def test_same_month_and_day(self):
        newer = "01/27/1832"
        older = "01/27/1756"
        self.assertEqual(get_earliest(newer, older), older)

    def test_february_29th(self):
        newer = "02/29/1972"
        older = "12/21/1946"
        self.assertEqual(get_earliest(newer, older), older)

    def test_smaller_month_bigger_day(self):
        newer = "03/21/1946"
        older = "02/24/1946"
        self.assertEqual(get_earliest(older, newer), older)

    def test_same_month_and_year(self):
        newer = "06/24/1958"
        older = "06/21/1958"
        self.assertEqual(get_earliest(older, newer), older)

    def test_invalid_date_allowed(self):
        newer = "02/29/2006"
        older = "02/28/2006"
        self.assertEqual(get_earliest(older, newer), older)

    def test_two_invalid_dates(self):
        newer = "02/30/2006"
        older = "02/29/2006"
        self.assertEqual(get_earliest(newer, older), older)

    def test_two_invalid_dates_v2(self):
        newer = "01/32/2007"
        older = "02/29/2006"
        self.assertEqual(get_earliest(newer, older), older)     

if __name__ == "__main__":
    unittest.main(argv=['first-arg-is-ignored'], exit=False)


    

    




.......
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Ran 7 tests in 0.003s

OK

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