Reference Error

What This Error Means

This error occurs when you try to use a variable that has not been assigned a value yet or has not been defined in the current scope.

Why It Happens

In Python, you must define a variable before you can use it. If you're trying to use a variable that is declared inside a function or block of code outside of that function or block, you'll get a NameError saying the variable is not defined.

How to Fix It

1. 1To fix this error, make sure to define the variable before using it. You can define a variable by assigning a value to it, like this: `total = 0`. If the variable is declared inside a function, make sure to call the function before using the variable.

Example Code Solution

total = price * quantity
print(total)

total = 0
total = price * quantity
print(total)