创建类时发生AttributeError

Question

这是我不知道的简单方法。创建此类时我做错了什么？ AttributeError发生在以下行：print（lunaLovegood.height_inches，'in，'，end =''）

class PatientData:
    def __init__(self):
        height_inches = 0
        weight_pounds = 0


lunaLovegood = PatientData()
print('Patient data (before):', end=' ')
print(lunaLovegood.height_inches, 'in,', end=' ')
print(lunaLovegood.weight_pounds, 'lbs')


lunaLovegood.height_inches = 63
lunaLovegood.weight_pounds = 115

print('Patient data (after):', end=' ')
print(lunaLovegood.height_inches, 'in,', end=' ')
print(lunaLovegood.weight_pounds, 'lbs')