def test_math_g02_unknowns(self): assert(mod.get_mean_length(self.unk_dict) == 1)
def test_math_g05_medium_sets(self): assert(mod.get_mean_length(self.med_dict_1) == 1.5)
def test_math_g01_emptiness(self): assert(mod.get_mean_length(self.empty_dict_1) is None)