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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

10 matches
Files & data medium

Chunk Large File Upload Simulation by Blocks in Python

A Python script reads a large binary file in fixed-size chunks and simulates a block-by-block upload with per-chunk SHA256 hashing.

file i/o chunking hashing
Python
import os
import hashlib
from pathlib import Path


def read_file_in_chunks(file_path, chunk_size=8196):
    """Yield chunks of a file as bytes."""
    with open(file_path, 'rb') as f:
        while chunk := f.read(chunk_size):
            yield chunk


def simulate_chunked_upload(file_path, chunk_size=8196):
    """S…
15 0 Open
Git + Python easy

Upload Assets to GitHub Release with Python Mock

Simulates uploading binary and text assets to a GitHub release using a mock server, returning structured metadata for each upload.

git github releases
Python
import json
import os
import tempfile
from datetime import datetime

class ReleaseUploader:
    """Simulates uploading assets to a release with a mock server."""
    
    def __init__(self, owner: str, repo: str, tag: str):
        self.owner = owner
        self.repo = repo
        self.tag = tag
        self.uploade…
12 0 Open
Cloud + Python medium

How to mock boto3 S3 upload file wrapper in Python

Wrap an S3 put_object call in a testable function that returns metadata, and mock boto3 to verify the upload without touching AWS.

boto3 s3 aws
Python
import boto3
import io


def upload_file_to_s3(file_obj, bucket, key, object_metadata=None):
    """Upload a file-like object to S3 and return a metadata dict."""
    s3 = boto3.client("s3")
    content = file_obj.read()
    s3.put_object(
        Bucket=bucket,
        Key=key,
        Body=content,
        Metadata=…
13 0 Open
Cloud + Python medium

How to mock boto3 S3 upload in Python

Shows how to mock the boto3 S3 client with unit tests and wrap an upload function to return a dictionary with status details.

boto3 s3 mocking
Python
import boto3
from unittest.mock import Mock, patch

class S3Uploader:
    def __init__(self, bucket_name):
        self.bucket_name = bucket_name
        self.s3 = boto3.client("s3", region_name="us-east-1")

    def upload_file(self, local_path, s3_key):
        self.s3.upload_file(local_path, self.bucket_name, s3_ke…
12 0 Open
Cloud + Python easy

Mock Azure Blob Upload and Download in Python

Simulate Azure Blob Storage upload and download operations with a lightweight in-memory mock class for testing.

azure mock testing
Python
import io
import json
from datetime import datetime, timezone

class MockBlob:
    def __init__(self, name):
        self.name = name
        self.content = b""
        self.properties = {
            "last_modified": datetime.now(timezone.utc).isoformat(),
            "size": 0,
        }

    def upload(self, data, …
14 0 Open
Cloud + Python medium

Mock GCP storage bucket blob upload in Python

Simulate uploading a blob to a GCP Storage bucket for testing without hitting the cloud.

gcp mock storage
Python
import io
from datetime import datetime
from unittest.mock import MagicMock, patch


class MockBlob:
    """Simulates a GCP storage blob for unit testing."""
    def __init__(self, name):
        self.name = name
        self.uploaded_at = None
        self.content = b""

    def upload_from_file(self, file_obj):
    …
14 0 Open
Modern tooling easy

How to Mock Twine Upload to TestPyPI in Python

Simulate a twine upload to TestPyPI with a dry-run mock function that validates distribution files and prints the intended upload action without any network call.

twine testpypi mock
Python
import subprocess
import sys

# Mock twine upload to TestPyPI using subprocess dry-run
def mock_twine_upload(dist_file: str, repo_url: str = "https://test.pypi.org/legacy/") -> None:
    """Simulate twine upload by checking dist file and printing intended action."""
    if not dist_file.endswith((".whl", ".tar.gz")):
…
12 0 Open
Modern tooling easy

Mock pdm build and publish in Python

Simulate pdm build and publish commands with unittest.mock to test packaging workflows without triggering real builds or uploads.

pdm mock unittest
Python
from unittest.mock import Mock, patch

import pdm


def build_package() -> str:
    """Simulate building a package with pdm."""
    build_mock = Mock(return_value="dist/mypackage-0.1.0-py3-none-any.whl")
    with patch.object(pdm, "build", build_mock):
        result = pdm.build()
    return result


def publish_packa…
12 0 Open
API design & gRPC medium

How to Parse Multipart Form Data in Python

Parse multipart/form-data uploads using the Python standard library's cgi module to extract both regular fields and file uploads.

multipart cgi form-data
Python
import cgi
from io import BytesIO

def parse_multipart_form(headers, body_bytes):
    content_type = headers.get("Content-Type", "")
    content_length = int(headers.get("Content-Length", len(body_bytes)))
    
    # Create a file-like object from bytes for cgi.FieldStorage
    body_file = BytesIO(body_bytes)
    
   …
13 0 Open
Production deployment patterns easy

How to Attach an SBOM to a Release in Python (Mock)

A mock function that attaches a Software Bill of Materials (SBOM) to a GitHub-style release by counting its components and marking the upload as attached.

sbom release json
Python
import json
from pathlib import Path


def attach_sbom_mock(sbom_path: Path, release_tag: str, artifact_name: str) -> dict:
    """Mock attaching an SBOM to a release, returning the simulated upload result."""
    sbom = json.loads(sbom_path.read_text())
    return {
        "release_tag": release_tag,
        "artifa…
13 0 Open

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  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

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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.