def test_identical_frequency_bands_have_same_hash_value(self):
fb1 = FrequencyBand.from_center(1000, 50)
fb2 = FrequencyBand.from_center(1000, 50)
self.assertEqual(hash(fb1), hash(fb2))
def test_can_create_from_center_frequency(self):
fb = FrequencyBand.from_center(1000, 50)
self.assertEqual(FrequencyBand(975, 1025), fb)
