how to keep asking user for right type of input if they type invalid input [duplicate]

Question

This program calculates depreciation

I want to keep asking user for input until it gives the valid input.

def CalculateDep(amount,nofYears,rate,yearOfPurchase):
    
    for i in range(nofYears):
        if (mop.lower() == "n" and i == 0):
            percentile = rate * 0.005
            
        elif(mop.lower() == "y" or mop.lower() == "n"):
            percentile = rate * 0.01
                      
        dep = round((percentile)*amount, 2)
        print("")                      # print blank line for readiblity
        print("Dep Charge @" + str(percentile*100) + " % : " + str(dep))
        print("On 31-03-" + str(yearOfPurchase+1))
        amount = amount - (dep)
        yearOfPurchase += 1 
        print("Value After Depreciation : " + str(round(amount, 2)))
        
    

amt = int(input("Enter the Amount : ")) #Initial value of asset
y = int(input("Enter the Number of years : ")) 
r =  float(input("Enter The depreciation Rate : "))
yop = int(input("Enter The Year in Which The Asset is purchased : "))
mop = input("Purchased asset before 1st October ? Answer y or n : ")


CalculateDep(amt, y, r, yop)

Answer 1

Typically this can be accomplished with a while loop

while True:
    try:
        amt = int(input("Enter the Amount : "))
    except ValueError:
        print('please enter an int')
    else:
        break