Python Projects for Beginners a ten-Week Bootcamp Approach to Python Programming

WEDNESDAY EXERCISES

1. 
   . Full Name: Create a function that takes in a first and last name and returns the two names joined together.
   
2. 
   . User Input: Within a function, ask for user input. Have this function return that input to be stored in a variable outside of the function. Then print out the input.
   

Today we learned how to retrieve information from a function. This will allow us to save the data it manipulates for later use.
Thursday: Scope
Today we’re going to discuss an important concept called scope. This concept deals with accessibility of variables declared within a program. We’ll go over the different types of scope and how to do handle them.
To follow along with this lesson, let’s continue from our previous notebook file
“Week_05” and simply add a markdown cell at the bottom that says, “Scope.”

Types of Scope

In Python, there are three types of scope: global, function, and class. We haven’t gone over classes just yet, so we’ll discuss class scope in a later chapter. Without knowing it, we’ve used the other two types of scope. Global scope is when you declare a variable to be accessible to an entire file or application. Most of the variables we’ve declared so far have been global; however, in most programs you write, you will want to avoid global variables. It’s okay in Jupyter Notebook for now though. Function scope is in reference to variables being declared and accessible only within functions. A variable declared inside of a function cannot be accessed outside of the function, as once the function terminates, so do the variables declared within it.

Global Scope Access

When global attributes are defined, they’re accessible to the rest of the file. However, we must keep in mind how function scope works. Even when you declare a variable accessible to the entire file, it will not be accessible within the function. Let’s see an example:

# where global variables can be accessed number = 5 def scopeTest( ):
number += 1 # not accessible due to function level scope scopeTest( )
CHapTeR 5 FUnCTIonS
Go ahead and run the cell. We’ll end up receiving an error because the function is limited to variables declared within it or passed in.
Note When passed in, it only passes the value, not the variable.