py_test_basics_example.py

class Country:
    """
    Convenience class for storing
    data relative to a given country

    """
    def __init__(self, country_name, population, continent):
        """
        Default constructor
        :param country_name:        str
        :param population:          float
        :param continent:           str
        """
        if not isinstance(country_name, str):
            raise ValueError("country_name param must be a string")
        if not isinstance(population, float):
            raise ValueError("population param must be a float")
        if not isinstance(continent, str):
            raise ValueError("continent param must be a string")

        self.country_name = country_name
        self.population = population
        self.continent = continent

    def get_population_in_millions(self):
        return round(self.population, 2)


def test_population():
    """
    Note: If the result is wrong, calling test_population
    will throw exception 'AssertionError'
    """
    country = Country("myFakeCountry", 10.0, "EU")
    expected = 10.00
    result = expected == country.get_population_in_millions()
    print("Test result = {res}".format(res=result))
    assert result

test_population()