Reference library

Python Code Samples

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

9 matches
AI & LLM integration patterns medium

Parse ReAct Logs into Thought Action Observation Steps in Python

Parse a ReAct agent's textual log into structured steps with thought, action, and observation using regex and named tuples.

react regex llm
Python
import re
from collections import namedtuple


ReActStep = namedtuple("ReActStep", ["thought", "action", "observation"])


def parse_react_log(log: str) -> list[ReActStep]:
    """Parse a ReAct log into structured thought/action/observation steps."""
    pattern = re.compile(
        r"Thought:\s*(?P<thought>.+?)\s*"
…
13 0 Open
Automation & scripting medium

Detect Circular Imports Across Python Projects Automatically

This script walks through all .py files in a directory, builds an import graph, and uses depth-first search to find cycles—printing each circular dependency chain.

circular-imports import-graph ast
Python
import ast
import sys
from pathlib import Path
from collections import defaultdict, deque

def find_imports(filepath):
    """Return set of module names imported by a Python file."""
    imports = set()
    try:
        with open(filepath) as f:
            tree = ast.parse(f.read())
    except (SyntaxError, UnicodeDe…
39 0 Open
Automation & scripting medium

Find Dead Code in a Python Project Using AST

Walk a project tree, parse every Python file with ast, and list defined functions that are never called anywhere.

ast dead-code static-analysis
Python
import ast
import os
import sys

def find_dead_code(project_path):
    defined_functions = {}
    called_functions = set()

    for root, dirs, files in os.walk(project_path):
        for file in files:
            if file.endswith('.py'):
                filepath = os.path.join(root, file)
                with open(f…
41 0 Open
Automation & scripting medium

Find Sensitive Information in Log Files with Python

Scan log files for emails, IP addresses, API keys, and passwords using regular expressions in Python.

regex security log-analysis
Python
import re
import os
from pathlib import Path

def find_sensitive_info(log_path):
    """Scans log files for patterns like emails, IPs, API keys, and passwords."""
    patterns = {
        'Email': r'[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}',
        'IP Address': r'\b(?:\d{1,3}\.){3}\d{1,3}\b',
        'API Key'…
37 0 Open
Automation & scripting medium

Find Unused Python Packages Automatically

Scan a Python project's source files for imports and list installed packages not imported anywhere.

unused-packages static-analysis ast
Python
import pkg_resources
import ast
import os
import sys
from pathlib import Path

def find_imports_in_project(project_dir="."):
    imports = set()
    for py_file in Path(project_dir).rglob("*.py"):
        try:
            with open(py_file, "r") as f:
                tree = ast.parse(f.read())
            for node in …
39 0 Open
Automation & scripting medium

How to Generate a Dependency Graph for Python Projects

This script walks through a Python project directory, parses each .py file's imports, and prints a dependency graph showing which modules depend on which other modules.

ast dependency graph import parsing
Python
import os
import ast
from pathlib import Path
from collections import defaultdict

def get_imports(filepath):
    with open(filepath) as f:
        try:
            tree = ast.parse(f.read())
        except SyntaxError:
            return []
    imports = []
    for node in ast.walk(tree):
        if isinstance(node, …
39 0 Open
Automation & scripting medium

How to Track GitHub Stars, Forks, and Watchers in Python

Automatically fetch and track stars, forks, and watchers for multiple GitHub repositories, saving snapshots locally as JSON files for historical analysis.

github api automation
Python
import os
import time
import json
import requests
from pathlib import Path
from datetime import datetime

REPOS = [
    "psf/requests",
    "python/cpython",
    "pallets/flask",
]
DATA_DIR = Path("github_metrics")

def fetch_repo_stats(repo):
    url = f"https://api.github.com/repos/{repo}"
    resp = requests.get(ur…
39 0 Open
Automation & scripting medium

How to check Python files for common coding mistakes

Walks a directory tree parsing each .py file with ast, reporting empty functions, bare try blocks, too many parameters, and empty classes.

ast linting code-quality
Python
import ast
import os
import sys

def check_file(filepath):
    try:
        with open(filepath) as f:
            code = f.read()
        tree = ast.parse(code, filename=filepath)
    except SyntaxError as e:
        print(f"{filepath}: SyntaxError: {e.msg}")
        return
    
    issues = []
    for node in ast.wal…
42 0 Open
A/B testing & experimentation medium

How to Perform Intent-to-Treat Analysis in Python

Runs an intent-to-treat analysis on mock A/B test data, comparing outcomes by initial group assignment with a t-test for significance.

ab-testing intent-to-treat statistics
Python
import pandas as pd
import numpy as np


def intent_to_treat_analysis(data):
    """Perform intent-to-treat (ITT) analysis.

    ITT compares outcomes based on initial treatment assignment,
    regardless of whether participants actually received the treatment.
    """
    # Create a copy to avoid mutating the origina…
13 0 Open

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