Common Python Errors and Practical Tips for Beginners

1. Cross‑platform code execution errors (IndentationError) – The author describes how mixing tabs and spaces in Notepad++ caused an IndentationError when the script was run on Linux, and how replacing tabs with four spaces and using an IDE such as PyCharm (which automatically converts tabs to spaces) resolved the issue.

2. Syntax errors involving spaces versus parentheses – A common mistake is using a space instead of parentheses with the print function. In Python 3.x, print requires parentheses, whereas Python 2.x allowed a space‑separated syntax. An illustration shows Python 3.10.1 for Windows enforcing the parentheses syntax.

3. Poor multithreading control can crash the machine – The author recounts a socket‑plus‑thread port‑forwarding program that, under heavy or long‑running data transfer, created an ever‑growing number of threads due to an infinite while loop, eventually exhausting system resources. Adding a timeout to limit thread creation is suggested.

4. Write code without thinking through logic first – The author outlines several lessons:

4.1. Data structures are a valuable discipline; reading classic algorithm books can provide reusable solutions.

4.2. Prefer built‑in methods (e.g., list.sort()) over manual implementations like bubble sort for better performance.

4.3. Plan the program logic with a flowchart before coding to avoid low efficiency and hard‑to‑trace bugs.

4.4. Avoid using unfamiliar constructs (e.g., lambda, map, reduce, Thread) in production code until you have practiced them in a test environment.

5. Python can do many things, but not everything is needed – The author experimented with numerous libraries (Django, WeChat, web scraping, database access, NodeJS‑to‑Python bridges, Tkinter, Qt, sockets, SSH). In practice, the most frequently used tools are Paramiko for SSH and a few basic modules. Clear objectives are essential for rapid development, as illustrated by small scripts that replace multi‑day manual tasks with a few hours of coding.

Original source: https://www.talkwithtrend.com/Article/259973