Question

__________ variables are defined outside all functions and are accessible to any function within their scope.

Short answer

Answer: Variables defined outside of functions are called global variables. These variables have a broader scope and can be accessed by any function within their scope. Functions can directly use and modify global variables with the help of the `global` keyword. However, relying heavily on global variables can make the code harder to maintain and understand. It's recommended to use function parameters and return values to manage variables instead.

Step-by-step solution

Understand the concept of variables outside functions

Variables that are defined outside of any function are called global variables. Global variables have a broader scope as compared to variables defined inside a function (local variables). A key characteristic of global variables is that they can be accessed by any function within their scope (i.e., within the same program or script).

Define a global variable

To better understand the concept, we will first define a global variable. A global variable is created by declaring a variable outside of any function. For example, consider the following variable declaration: ```python x = 10 ``` In this example, `x` is a global variable with the value of 10.

Access the global variable from a function

Now that we have a global variable, let's create a function to access this variable. Functions can directly use the global variable as if it were a local variable, like so: ```python x = 10 # Global variable def print_global_variable(): print("Global variable x =", x) print_global_variable() ``` When this code runs, the output will be: ``` Global variable x = 10 ```

Global variables and function interaction

Functions can also modify global variables. However, to do so, we need to use the `global` keyword inside the function. This tells the function that we are referring to the global variable, not a local one. Here's an example: ```python x = 10 # Global variable def modify_global_variable(): global x x = x + 5 print("Before modification:", x) modify_global_variable() print("After modification:", x) ``` This code will output: ``` Before modification: 10 After modification: 15 ``` Keep in mind that using too many global variables can make the code harder to maintain and understand. It's better to pass the variables as parameters to functions and have them return modified values if needed.