Hello, I’m new to Codecademy and I’m struggling with the project on Medical Insurance Cost for the lesson on Python functions.

Here is my code:

# Create calculate_insurance_cost() function below:

def calculate_insurance_cost(age, sex, bmi, num_of_children, smoker, name):

estimated_cost = 250*age - 128*sex + 370*bmi + 425*num_of_children + 24000*smoker - 12500

output = print(“The estimated insurance cost for " + name + " is " + str(estimated_cost) + " dollars”)

return output, estimated_cost

# Estimate Maria’s insurance cost

maria_insurance_cost = calculate_insurance_cost(28, 0, 26.2, 3, 0, “Maria”)

# Estimate Omar’s insurance cost

omar_insurance_cost = calculate_insurance_cost(35, 1, 22.2, 0, 1, “Omar”)

# Estimate John’s insurance cost

john_insurance_cost = calculate_insurance_cost(28, 1, 28, 0, 0, “John”)

# Estimate differences in insurance cost between Maria and Omar

def calculate_insurance_cost_1(age, sex, bmi, num_of_children, smoker):

estimated_cost = 250*age - 128*sex + 370*bmi + 425*num_of_children + 24000*smoker - 12500

maria_insurance_cost_1 = calculate_insurance_cost_1(28, 0, 26.2, 3, 0)

omar_insurance_cost_1 = calculate_insurance_cost_1(35, 1, 22.2, 0, 1)

def different_insurance_cost(maria_cost, omar_cost):

diff_insurance_cost = maria_insurance_cost_1 - omar_insurance_cost_1

print(“The difference in insurance cost is " + diff_insurance_cost + " dollars.”)

different_insurance_cost(maria_insurance_cost_1, omar_insurance_cost_1)

It’s giving the following error but I’m not sure why: TypeError: unsupported operand type(s) for -: ‘NoneType’ and ‘NoneType’. Could anyone help on this? thank you!