Write function bmi that calculates body mass index (bmi = weight / height ^ 2).
if bmi <= 18.5 return "Underweight"
if bmi <= 25.0 return "Normal"
if bmi <= 30.0 return "Overweight"
if bmi > 30 return "Obese"
def bmi(weight, height):
    a = weight / height ** 2
    if a <= 18.5:
        return "Underweight"  
    elif a <= 25.0:
        return "Normal"
    elif a <= 30.0:
        return "Overweight"
    elif a > 30:
        return "Obese"
    return "You are Grasshopper"
    #your code here

def bmi(weight, height):
    a = weight / height ** 2
    if a <= 18.5:
        return "Underweight"  
    elif a <= 25.0:
        return "Normal"
    elif a <= 30.0:
        return "Overweight"
    elif a > 30:
        return "Obese"
    return "You are Grasshopper"
    #your code here
