教教孩子怎么改写函数吧

def zhelishimingzi(height, weight):
height, weight = int(height), int(weight)
bmi = weight / (height * height)
who, dom = "", ""
if bmi < 18.5:
who, dom = "偏瘦", "偏瘦"
elif 18.5 <= bmi < 24:
who, dom = "正常", "正常"
elif 24 <= bmi < 25:
who, dom = "正常", "偏胖"
elif 25 <= bmi < 28:
who, dom = "偏胖", "偏胖"
elif 28 <= bmi < 30:
who, dom = "偏胖", "肥胖"
else:
who, dom = "肥胖", "肥胖"
return "BMI={:.2f}，指标为：国际{}-国内{}".format(bmi, who, dom)
height = input("height:").strip()
weight = input("weight:").strip()
print(zhelishimingzi(height, weight))