Question

How do modules help you reuse code in a program?

Short answer

Answer: Modules help in reusing code by allowing programmers to group related functions and variables, which can be imported into other programs using the 'import' statement. This promotes cleaner, more efficient code development and maintenance. To use modules effectively: (1) Understand the concept of modules as reusable code, (2) Embrace code reusability, (3) Create a module by writing related code in a separate file, then import the module using 'import' statement, and (4) Utilize built-in modules for common functionalities.

Step-by-step solution

1. Understanding Modules

Modules are reusable pieces of code that can be imported into other programs to provide additional functionality without having to rewrite the same code multiple times. They contain functions, variables, and other objects that can be used in other programs, making code development more efficient and manageable.

2. Code Reusability

One of the main benefits of using modules is code reusability. By organizing related code as modules, we can avoid duplicating code in different parts of the same program or in different programs. This promotes easier maintenance, improved readability, and consistent functionality across projects.

3. Creating and Importing Modules

To create a module, we simply need to write the related code in a separate file (e.g., 'module_name.py'). Then, we can use the 'import' statement in other programs to include the functionalities provided by this module. For example, to import a module named 'example_module', we can use the following syntax: ```python import example_module ``` We can then access the module's functions and variables by using the module name followed by a dot and the required object name, like this: ```python example_module.function_name() # Call the function_name from the imported module ```

4. Built-in Modules

Python provides many built-in modules that include common, prewritten functionalities. These modules can be imported just like any other custom module. Some popular built-in modules are 'math', 'random', and 'datetime'. For example, to import the 'math' module, which includes various mathematical functions, we can use the following syntax: ```python import math print(math.sqrt(25)) # Outputs the square root of 25 ``` In summary, modules help in reusing code by providing a way to group related code and functions, enabling the programmer to use these functionalities in other programs with the help of the 'import' statement. This promotes cleaner, more efficient code development and maintenance.