The World of Python Programming

Complete Guide to Writing, Running & Using Python Scripts

Common Questions & Tips
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1. Introduction

Python is one of the programming languages that has rapidly grown in popularity in recent years. In particular, Python scripts allow automation and data processing with simple code, making them widely used by everyone from beginners to experts. This article explains in detail everything from the basics of Python scripts to advanced uses, and provides information useful both for those new to Python and those who already have experience. The goal of this article is to provide a comprehensive understanding of how to write Python scripts, how to run them, examples of practical applications, and even how to distribute them. By mastering Python scripting, you’ll be able to turn your ideas into concrete programs and automate tasks in your daily work or personal projects. We’ll explain everything step by step, so please read through to the end.

2. What is a Python script?

A Python script refers to a sequence of code written in the Python programming language. Scripts are saved as files and, when executed, automatically carry out the specified actions. For example, they can be applied to tasks such as data aggregation, file operations, or simple games. Python scripts are characterized by their simple, readable syntax combined with a powerful standard library. Compared to other programming languages, they are intuitive and let you write programs in fewer lines of code, making them suitable for beginners. Additionally, once a script is created, it can be reused repeatedly, making it ideal for automating routine tasks.
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3. Basics of Writing Python Scripts

Basic Syntax

The basic syntax of Python scripts is very simple. In Python, code structure is expressed using indentation, which makes it easy to write clear, well-organized code.

Declaring Variables

In Python, you don’t need to specify a type when declaring variables. You can declare them simply like this.
name = "Python"
version = 3.9

Control Structures (if statements, loops)

In Python scripts, control structures let you perform conditional branching and repetition.
if Statement Example
age = 18
if age >= 18:
    print("You are an adult.")
else:
    print("You are a minor.")
for Loop Example
for i in range(5):
    print(i)
As you can see, Python’s charm is that you can express conditional branching and loops with concise syntax.

4. How to Run Python Scripts

There are several ways to run Python scripts; use the method that best fits your environment and needs.

Running from the command line

The most basic method is to run the script from the command line (terminal). You can run a Python script by entering the following command:
python script.py

Differences by operating system

  • Windows: Run the above command in Command Prompt or PowerShell.
  • macOS: Type python3 script.py in the terminal.
  • Linux: As with macOS, run it from the terminal.

Running in an IDE or editor

Many programmers run Python scripts using IDEs like PyCharm or VS Code. These tools offer features such as debugging and autocomplete, making development more efficient.
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5. Applications of Python Scripts

Python scripts are used in many situations in business and everyday life. Here are a few examples of their applications.

Automating Data Processing

Using Python scripts for data collection, processing, and analysis can automate time-consuming tasks. For example, scripts that aggregate data from CSV files or web-scraping scripts that gather information from the web are common.

Sample Code

import csv

with open('data.csv', 'r') as file:
    reader = csv.reader(file)
    for row in reader:
        print(row)
This code is a simple example that reads data from a CSV file and displays it.

6. Distributing Python Scripts and Creating Executables

It’s also important to have methods to run the Python scripts you create in other environments.

Creating EXE Files

By converting a Python script into an executable (exe), you can run it on systems where Python isn’t installed. Tools like PyInstaller and cx_Freeze make this conversion easy.

Example: Using PyInstaller

pip install pyinstaller
pyinstaller --onefile script.py
When you run this command, an executable file will be created in the dist folder.

7. Best Practices for Python Scripts

Here are best practices for efficiently writing Python scripts.

Coding Conventions (PEP 8)

Python has a coding convention called PEP 8 that lists rules to follow to improve code readability. For example, it is recommended to use snake_case (my_variable) for function and variable names.

Sample Code

def calculate_total(price, tax):
    return price + (price * tax)
Writing readable code is important because it makes future maintenance easier.

8. Summary

We’ve explained Python scripting from the basics through advanced topics. Leveraging Python scripts can boost efficiency in everyday tasks and hobby projects, and let you enjoy programming. Python is easy to learn and highly versatile, so go ahead and give it a try.