Step 1

• Create a new Python file in PyCharm by right-clicking the project you created and selecting New > Python File.

Step 2

• Declare the variable product and assign it an integer value of 1.

product = 1

Step 3

• Create a for loop that performs four iterations.

for i in range(4):

Step 4

• In the for loop, ask the user to provide a number, cast that number to an integer, and assign it to a new variable. Multiply each input by the product variable and assign the result to the same variable.

    num = int(input("Enter a number: "))
    product *= num

Step 5

• Place the user input and mathematical operation in a try block. Make sure that you use indentation when placing it in the try block.

    try:
        num = int(input("Enter a number: "))
        product *= num

Step 6

• Create an except block that prints a message to the console when user input is a non-integer.

    except :
        print("The input is not a valid number")

Step 7

• Run the code from Step 6, input an integer, then input a non-integer, and observe the results.
• The last input, as shown below, is a non-integer. The error is caught by the except statement in the try block and triggers the invalidation message to appear.

Step 8

• Add a line to print the four numbers' product and cast the integer to a string.

print("The product of the 4 numbers is: "+ str(product))

Step 9

• Rerun the code, but this time input integers only. Observe the results.

Final Code

"""Lab Objective: Practice handling errors that may occur in the code."""

product = 1
for i in range(4):
    try:
        num = int(input("Enter a number: "))
        product *= num
    except:
        print("The input is not a valid number")
print("The product of the 4 numbers is: " + str(product))

print(product)

# prevents program from closing upon execution
input("\nPress 'Enter' to exit the program")