if elif else program python

Shipping charges for an online orders are based on the value of the order and the shipping weight. Shipping is free if the value is over $100. Orders under $100 incur shipping charges as follows: Over 40 lbs: $1.09 per lb. Over 20 lbs: $0.99 per lb. Equal to or Under 20 lbs: $0.89 per lb. I need to write a python program that prompts the user to enter both the value and weight of an order, then displays the required shipping charges. But if the order value is $100 or more, weight is irrelevant and your program should not ask for it.

SO far I have figure out the coding for the shipping not sure about the other parts.

#Have user enter weight of order
weight = int(input('Enter the weight of your order:'))

#Determine shipping cost
if weight >= 40:
    total = weight * 1.09
elif weight >= 20:
    total = weight * 0.99
elif weight <=20:
    total = weight * 0.89

Thank you for your help!