Python CLI Tricks: Using -m Modules, Port Testing, Simple Web Server, JSON Formatting, Text Editor, Executable Packaging, Encoding/Decoding, System Info, and File Compression

We start with the Python CLI and the python --help command to list available options, highlighting the -m mod flag which runs a module as a script.

1. Service Port Testing – Instead of installing telnet, Python’s telnetlib module can test outbound ports. Example: python -m telnetlib -d 142.250.70.174 443 shows a successful connection, while using an invalid port (e.g., 999) raises an error.

2. Launching a Local Web Server – A quick static server can be started with python -m http.server , which listens on port 8000 and serves files from the current directory, useful for sharing local resources.

3. Validating and Formatting JSON Strings – Long, unformatted JSON can be prettified using the built‑in json.tool module: echo '{"name": {"first_name":"Chris", "last_name":"Tao"} "age":33}' | python -m json.tool . Adding a missing comma fixes the JSON and produces nicely indented output.

4. Creating a Simple Text Editor – Using the idlelib module (Tkinter‑based), a minimal UI editor can be launched: mkdir get_time_app && python -m idlelib get_time_app/print_time.py . The editor supports syntax highlighting and can be saved with Ctrl+S .

5. Building an Executable Application – Python’s zipapp module packages a directory into a single .pyz file: python -m zipapp get_time_app -m "print_time:main" . The resulting file runs via python get_time_app.pyz .

6. Encoding and Decoding Strings or Files – Demonstrations include ROT13 encryption with encodings.rot_13 , base64 encoding/decoding ( echo "I am Chris" | python -m base64 and echo "SSBhbSBDaHJpcwo=" | python -m base64 -d ), and encoding a script file for later execution.

7. Retrieving System Metadata – The python -m sysconfig command displays full Python configuration; python -m site shows environment paths and the current working directory.

8. File Compression – Python can create and extract zip archives without external tools: python -m zipfile -c get_time_app.zip get_time_app to compress, and python -m zipfile -e get_time_app.zip get_time_app_extracted to extract, followed by verification of extracted files.