def emc2(mass):
    """
    function that gets the energy equivalence of a given mass in kilograms using Einstein's e=mc2 equation
    and returns the energy equivalence (e) in joules

    :param mass: mass is the mass of the object in kilograms
    :return: returns e, as mass energy equivalence measured in joules
    """
    return mass * 299792458 ** 2
