Understanding the Structure of a Python Program
A beginner’s guide
Introduction
In this beginner’s guide, we’ll be looking at everything you need to know about how to write readable and maintainable code in Python. We’ll start by learning what a Python program is, then move on to functions and variables. After that, we’ll discuss organization of code as well as layout. Lastly we’ll dive into execution of code before wrapping everything up with some tips on how to debug your programs!
In this article, we’ll be looking at everything you need to know about how to write readable and maintainable code in Python.
Python is a high-level programming language, which means that it’s designed to make your life easier. It’s an object oriented language, meaning that objects (like numbers and strings) are the main building blocks that you’ll be working with throughout your code.
Python is dynamic in nature because it allows you to change the values of variables at runtime — for example if you want to add two numbers together at runtime instead of doing it sequentially like we do in math class when we did long division.
Python has been around since 1991! The creators originally used this name because they wanted something simple enough for beginners without being too complicated yet powerful enough for experts as well; hence why we call ourselves “pythons”.
What is a Python program?
A Python program is a set of instructions that tell the computer what to do. Programs can be written in many different programming languages, but Python is one of the easiest to learn.
Python programs are made up of three parts:
- One or more modules (the files containing your code)
- Statements (the body of your program)
Functions
A function is a reusable code block that can be used to break down a large program into smaller pieces. You’ll use functions to reduce redundancy, make your code more readable and share common parts of your program with other programmers.
Functions are like mini-programs in that they perform specific tasks and return a value (usually data). But unlike programs, which run continuously until they’re stopped by the computer’s operating system or terminated by an external event such as pressing Ctrl+C (^C), functions have defined ends: when their execution is complete, they either return control back to the caller or stop running altogether.
Variable naming conventions
You may be wondering why it’s important to use a naming convention. The answer is simple: it helps you and others understand what your program is doing.
A good naming convention is one that communicates clearly and accurately. In this tutorial, we’ll go over some ways to help you choose a good name for your variables, as well as how they’re used in Python programs.
Code organization
It’s important to understand that code organization is not just about the layout of your code. It’s also about how you structure your code, and how you name your variables and functions.
The way you organize your source files will have an impact on their readability and maintainability in the long run. This can be especially true if you’re working on a large project with many contributors or users who may not share the same coding conventions as yourself (or each other).
You’ll want to make sure that every function has its own module file so that it can be used independently from other parts of your program without needing imports from another module or file first before calling it in another part elsewhere within those same modules themselves; this helps reduce duplication between functions when writing them back later on down into actual production releases which companies often choose do so themselves instead because they know these things only benefit them greatly over time since there isn’t too much overhead involved beyond simply being able access any given piece(s) needed immediately upon request — especially when dealing with large amounts like those found within automobile manufacturing plants such as Chrysler LLC
Code layout
Code layout is the arrangement of code in a file. It’s important for readability and maintainability, but it can be confusing to understand how to do it correctly.
Python code layout is typically organized into modules, with each module containing multiple functions (or procedures), which are called methods. The contents of these functions are then used to build up larger structures out of smaller ones; for example, if you have a function called sum() that computes the sum of two numbers x and y using addition as its operation, then your program might contain another function called multiply() that multiplies those same numbers (x and y) together:
sum(y) = x * y
Code execution
Now that you understand the structure of a Python program and how Python programs are executed, let’s look at how to write them.
A Python program is executed from top to bottom, line by line. This means that the first statement in your code will be executed before any other statements (if there are any), so if you want your program to do something other than run from start to finish, you’ll need some kind of loop or conditional statement after it executes all its statements and reaches its last line. A simple example might be:
```python print(“Hello World!”)```
Program flow
Program flow is the order in which your program executes its individual statements, and it determines what happens as a result.
There are two basic approaches to programming: iterative and recursive.
Iterative programming is when you repeat a process until a condition is met. This is usually done with loops or “if” statements. Recursive programming is when you call a function from within itself and keep doing so until a certain condition is met.
Conclusion
We hope you now have an understanding of the structure of a Python program, and feel more confident about writing code that’s easy to read and maintain.
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