Run Multiple Cells in Jupyter: Safe, Repeatable Workflows
Run multiple Jupyter cells with Run All, selected ranges, restart-and-run, checkpoints, notebook execution, and reproducible workflows.
Tutorials
Browse Python tutorials for beginners and working developers, including syntax, libraries, examples, projects, and real problem-solving guides.
ast.literal_eval in Python: Safe Literal Parsing
Parse trusted Python literal data with ast.literal_eval, understand its limits, and choose JSON or a safer boundary for untrusted input.
Python __all__: Control Wildcard Imports and Public Names
Understand Python __all__ for module exports, wildcard imports, package APIs, re-exports, naming, and maintainable public interfaces.
Python SortedDict: Sorted Containers, Keys, and Updates
Use SortedDict from sortedcontainers for sorted keys, range-friendly access, updates, deletion, and a clear comparison with dict.
Generate a Symmetric Key with OpenSSL and Python Safely
Generate and use symmetric keys with OpenSSL and Python while avoiding shell injection, protecting key material, handling nonces, and validating encryption workflows.
Make requirements.txt in Python: Freeze and Install Dependencies
Create a useful Python requirements.txt with virtual environments, version constraints, pip freeze, reproducible installs, and safer project metadata.
Convert Unix Time to Datetime in Python: Time Zones and Units
Convert Unix timestamps to Python datetime values with seconds or milliseconds, UTC, time zones, validation, and daylight-saving considerations.
Python virtualenv Location: Find, Create, and Verify Environments
Find a Python virtualenv location with sys.prefix and pathlib, create predictable environments, verify the active interpreter, and avoid package confusion.
Tokenize a String in Python: split(), Regex, CSV, and NLP
Tokenize strings in Python with split(), regular expressions, shlex, CSV parsing, and NLP tools by matching the tokenizer to the input grammar.
Print to stderr in Python: sys.stderr and Logging
Print diagnostics to stderr in Python with print(), sys.stderr, and logging while keeping stdout clean for pipelines and tests.