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How to Build a Zero-Shot Classification Prompt in Python
Creates a prompt for zero-shot text classification by pairing input text with candidate labels and a hypothesis template.
from typing import Dict, List
def build_zero_shot_prompt(
text: str,
candidate_labels: List[str],
hypothesis_template: str = "This is about {}.",
) -> Dict[str, List[str]]:
"""Build a prompt ready for zero-shot classification."""
return {
"sequences": text,
"candidate_labels": can…How to Build an Agent Loop with Plan, Act, Observe in Python
Implements a simple plan-act-observe loop that an AI agent uses to iteratively complete a task in an environment while storing observations in memory.
class Agent:
def __init__(self, name):
self.name = name
self.memory = {}
def plan(self, task):
return f"Plan for {task}: step 1, step 2, step 3"
def act(self, plan, environment):
return f"Executing {plan} in {environment}"
def observe(self, action_result):
sel…How to Build an Entity Memory Dict to Store Facts in Python
Store and recall facts about entities using nested dictionaries with remember, recall, and forget functions in Python.
facts = {}
def remember(entity, attribute, value):
if entity not in facts:
facts[entity] = {}
facts[entity][attribute] = value
def recall(entity, attribute):
return facts.get(entity, {}).get(attribute, None)
def forget(entity, attribute=None):
if attribute is None:
facts.pop(entity, …How to Build an In-Memory Vector Store in Python
Build a lightweight in-memory vector store using a Python dict and cosine similarity for fast nearest-neighbor searches.
import math
from typing import Dict, List, Optional
class InMemoryVectorStore:
def __init__(self) -> None:
self.vectors: Dict[str, List[float]] = {}
self.index: Dict[str, List[str]] = {} # query -> list of ids sorted by similarity
def add(self, vector_id: str, vector: List[float]) -> None:
…How to build a function calling schema dict in Python
Build an OpenAI-compatible function calling schema dictionary with a helper function that takes name, description, parameters, and required fields.
import json
from typing import Dict, Any, List, Optional
def build_function_schema(
name: str,
description: str,
parameters: Optional[Dict[str, Any]] = None,
required: Optional[List[str]] = None
) -> Dict[str, Any]:
"""Build an OpenAI-compatible function calling schema dictionary."""
schema: …How to build a mock RAG pipeline in Python
Build a minimal Retrieval-Augmented Generation pipeline that retrieves the best-matching document by keyword overlap and generates a template-based answer.
def simple_rag_pipeline(question, documents):
"""
A minimal mock RAG pipeline: retrieve relevant context, then generate an answer.
"""
# Step 1: Retrieve — mock retrieval by simple keyword scoring
scores = []
for doc in documents:
doc_words = set(doc.lower().split())
question_wo…Prepare LLM prompt data with a Python helper class
A beginner-friendly Python class that collects records, converts them to JSON, and produces a quick summary for building LLM prompt context.
import json
from typing import Any, Dict, List
class DataHelper:
"""Simple helper to prepare data for LLM prompts."""
def __init__(self):
self.data = []
def add(self, item: Dict[str, Any]) -> "DataHelper":
self.data.append(item)
return self
def to_json(self) -> s…Build a Command-Line Password Generator in Python
Generate cryptographically strong random passwords using Python's secrets module and print them for command-line use.
import secrets
import string
def generate_password(length=16):
"""Generate a cryptographically strong random password."""
alphabet = string.ascii_letters + string.digits + string.punctuation
password = ''.join(secrets.choice(alphabet) for _ in range(length))
return password
if __name__ == "__main__":…Build a Live Countdown Timer for Events in Python
A Python script that displays a real-time countdown to a target date and time, updating every second in the console.
import datetime
import time
def countdown(event_name, target_datetime):
"""Displays a live countdown to a target datetime."""
while True:
now = datetime.datetime.now()
remaining = target_datetime - now
if remaining.total_seconds() <= 0:
print(f"\n🚀 {event_name} is happening…Build an M3U Playlist from Folder MP3s in Python
Scans a folder for MP3 files and writes a valid M3U playlist with absolute file URIs.
from pathlib import Path
import sys
def build_playlist(folder: str, output: str = "playlist.m3u") -> str:
folder_path = Path(folder)
if not folder_path.is_dir():
raise FileNotFoundError(f"Folder not found: {folder}")
mp3_files = sorted(folder_path.glob("*.mp3"))
if not mp3_files:
pri…Create Mock Watermarked Image Bytes in Python Without PIL
Builds a mock image-like byte stream with an embedded watermark using only stdlib modules, for testing pipelines without PIL.
from io import BytesIO
import zlib
import struct
def create_watermarked_bytes(width: int, height: int, watermark: bytes) -> bytes:
"""Create a mock image-like byte stream with a watermark (no PIL)."""
header = struct.pack("<2I", width, height)
payload = watermark * max(1, (width * height // max(1, len(wa…Fetch weather API mock and write dashboard HTML in Python
This script fetches a mock weather API response as a Python dict, builds a simple HTML dashboard, writes it to a file, and prints both the file path and JSON payload.
from datetime import datetime
import json
import os
def fetch_weather_mock(city: str) -> dict:
"""Return a mock weather payload for a given city."""
return {
"city": city,
"temperature_c": 21.5,
"condition": "Partly Cloudy",
"humidity": 58,
"wind_kph": 12.3,
"u…Generate Strong Random Passwords with Custom Rules in Python
Build a configurable password generator using Python's secrets module that lets you toggle lowercase, uppercase, digits, and punctuation.
import secrets
import string
def generate_password(length=16, use_lower=True, use_upper=True, use_digits=True, use_punct=True):
pool = ''
if use_lower:
pool += string.ascii_lowercase
if use_upper:
pool += string.ascii_uppercase
if use_digits:
pool += string.digits
if use_pu…How to Build a CLI with argparse in Python
Create a beginner-friendly command-line tool in Python that processes multiple filenames with optional flags for verbose output and uppercase conversion.
import argparse
def main():
parser = argparse.ArgumentParser(
description="A simple CLI to process files with optional verbose mode."
)
parser.add_argument("filenames", nargs="+", help="Files to process")
parser.add_argument("-v", "--verbose", action="store_true", help="Print extra details")
…How to Build a Docker Image Tag Script in Python
Generate consistent Docker image tags from service names and versions with automatic normalization.
#!/usr/bin/env python3
"""Mock script for building docker image tags."""
def build_tag(service_name: str, version: str, registry: str = "docker.io") -> str:
"""Construct a docker image tag."""
safe_name = service_name.lower().replace("_", "-")
return f"{registry}/{safe_name}:{version}"
if __name__ == "…How to Build a Python argparse CLI for Beginners
Build a beginner-friendly command-line interface using Python's argparse module with positional and optional arguments.
import argparse
def greet(name, greeting="Hello", uppercase=False):
message = f"{greeting}, {name}!"
if uppercase:
message = message.upper()
return message
def main():
parser = argparse.ArgumentParser(description="A simple CLI greet tool for beginners.")
parser.add_argument("name", help="…How to Build a Simple Python CLI with argparse
Create a friendly command-line greeting tool with argparse that accepts a positional name and optional flags for custom greetings and uppercase output.
import argparse
def greet(name, greeting="Hello", uppercase=False):
message = f"{greeting}, {name}!"
return message.upper() if uppercase else message
if __name__ == "__main__":
parser = argparse.ArgumentParser(
description="A simple greeting tool to demonstrate argparse basics."
)
parser.…How to Build a Simple argparse CLI in Python
Create a beginner-friendly command-line tool with argparse that reads a file, optionally uppercases its lines, and prints a configurable number of lines.
import argparse
def main():
parser = argparse.ArgumentParser(
description="Automate file processing with a simple CLI tool."
)
parser.add_argument("filename", help="Path to the input file")
parser.add_argument("--uppercase", action="store_true", help="Convert text to uppercase")
parser.add…How to Build a Simple argparse CLI in Python
Build a beginner-friendly command-line tool with argparse that greets a user, with optional greeting text and uppercase output.
import argparse
def greet(name, greeting="Hello", uppercase=False):
message = f"{greeting}, {name}!"
if uppercase:
message = message.upper()
return message
if __name__ == "__main__":
parser = argparse.ArgumentParser(description="Simple CLI greeting tool")
parser.add_argument("name", help=…How to Build an argparse CLI That Filters File Lines by Keyword in Python
This Python script is a command-line tool built with argparse that reads a text file and prints only the lines that contain (or don't contain) a given keyword.
import argparse
import sys
def main():
parser = argparse.ArgumentParser(description="Filter lines from a file by keyword.")
parser.add_argument("input", type=str, help="File to read")
parser.add_argument("keyword", type=str, help="Keyword to filter lines")
parser.add_argument("--contains", action="sto…How to Build an argparse Command-Line Tool in Python
Create a simple file-info CLI with argparse that counts lines and prints file size, with optional verbose and output flags.
import argparse
import os
from pathlib import Path
def process_file(filepath, verbose=False):
"""Read a file and report its size and line count."""
path = Path(filepath)
if not path.exists():
raise FileNotFoundError(f"File not found: {filepath}")
content = path.read_text()
lines = conten…How to Create a Simple Python CLI with argparse
Build a beginner-friendly command-line tool with argparse that accepts positional and optional arguments to greet users flexibly.
import argparse
def greet(name, greeting="Hello", uppercase=False):
message = f"{greeting}, {name}!"
return message.upper() if uppercase else message
def main():
parser = argparse.ArgumentParser(
description="A simple CLI tool that greets users."
)
parser.add_argument(
"name",
…How to Deploy a Static Site Build to an Nginx Directory in Python
Copy a static site build directory into an Nginx web root using Python's shutil and pathlib modules.
import shutil
import os
from pathlib import Path
SRC_DIR = Path("build")
DEST_DIR = Path("/var/www/html")
def deploy_site(src: Path, dest: Path) -> None:
if not src.exists():
raise FileNotFoundError(f"Build directory not found: {src}")
dest.mkdir(parents=True, exist_ok=True)
for item in src.ite…How to Implement argparse CLI Command in Python
Build a beginner-friendly command-line tool with argparse that accepts positional and optional arguments, flags, and prints a customizable greeting.
import argparse
def main():
parser = argparse.ArgumentParser(description="A simple CLI tool to greet users.")
parser.add_argument("name", help="Your name")
parser.add_argument("-g", "--greeting", default="Hello", help="Greeting word (default: Hello)")
parser.add_argument("--uppercase", action="store_…Browse by section
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