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Python Code Samples

Easy snippets you can copy, study, and run in the browser editor.

4 matches
Files & data easy

Convert CSV Files to JSON in Python

Convert a CSV file to a JSON file using Python's built-in csv and json modules.

csv json conversion
Python
import csv
import json

def csv_to_json(csv_filepath, json_filepath):
    """Convert a CSV file to a JSON file."""
    with open(csv_filepath, mode='r', newline='') as csv_file:
        reader = csv.DictReader(csv_file)
        data = [row for row in reader]

    with open(json_filepath, mode='w') as json_file:
      …
43 0 Open
Files & data easy

Detect Outliers in CSV Data Using Z-Score in Python

Read a CSV file and detect outliers in a numeric column by computing z-scores, flagging those exceeding a given threshold — no machine learning required.

outlier-detection z-score csv
Python
import csv
import statistics
from math import sqrt

def detect_outliers(csv_path, column_name, threshold=2.0):
    """Detect outliers in a numeric column using z-score method."""
    values = []
    with open(csv_path, 'r', newline='') as f:
        reader = csv.DictReader(f)
        if column_name not in reader.field…
19 0 Open
Files & data easy

Split CSV Files into Smaller Chunks in Python

Splits a large CSV file into multiple smaller chunk files, preserving the header row in each chunk.

csv file-splitting batch-processing
Python
import csv
import os

def split_csv(input_file, chunk_size=1000, output_prefix="chunk"):
    """Split a large CSV file into smaller chunks."""
    with open(input_file, 'r', newline='') as infile:
        reader = csv.reader(infile)
        header = next(reader)
        
        file_count = 1
        row_count = 0
  …
23 0 Open
Automation & scripting easy

Automatically Log CPU, RAM, and Disk Usage Every Minute in Python

This script logs CPU, RAM, and disk usage to a CSV file every 60 seconds using psutil and Python's standard library.

psutil automation monitoring
Python
import psutil
import time
import csv
from pathlib import Path

LOG_FILE = Path("system_usage_log.csv")
INTERVAL_SECONDS = 60

def log_system_usage():
    """Write CPU, RAM, and disk usage to CSV every minute."""
    file_exists = LOG_FILE.exists()
    with open(LOG_FILE, mode="a", newline="") as f:
        writer = cs…
24 0 Open

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Guide: free Python code samples library

Copy-ready Python snippets for learners and developers

PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

How to use this library

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.