Python setattr(): Set Object Attributes Dynamically and Safely
Use Python setattr() to set dynamic object attributes, understand properties and __slots__, validate names, and choose mappings when keys are data.
Tutorials
Browse Python tutorials for beginners and working developers, including syntax, libraries, examples, projects, and real problem-solving guides.
Tabulate JSON in Python: Flatten, Format, and Validate Data
Display JSON data as Python tables with tabulate by normalizing records, choosing columns, handling nested values, missing keys, and safe output.
Rotate and Scale a Vector in Python With Matrices
Rotate and scale 2D vectors in Python with NumPy matrices, radians, composition order, homogeneous transforms, and clear coordinate-system checks.
Mock a Context Manager in Python with unittest.mock
Mock Python context managers with MagicMock, __enter__, __exit__, patch targets, exception behavior, and readable tests.
Read a File Line by Line in Python: Efficient and Safe Patterns
Read files line by line in Python with context managers, iteration, encodings, newline handling, memory limits, and error-aware processing.
Python range() Inclusive Stop: Positive and Negative Steps
Python range() excludes stop; include an endpoint by adjusting the boundary for the step direction and testing the resulting sequence.
Python datetime.now(): Local Time, UTC, and Time Zones
Use Python datetime.now() correctly with local time, UTC, timezone-aware values, formatting, and daylight-saving transitions.
Python Shebang: Run Scripts with the Intended Interpreter
Write a portable Python shebang with env or an explicit interpreter, make scripts executable, diagnose interpreter paths, and understand Windows behavior.
Python Multiline Strings: Triple Quotes, Newlines, and Indentation
Use triple quotes for retained newlines, implicit concatenation for readable long text, and dedent when source-code indentation should not become content.
Python %s Formatting: Placeholders, Tuples, and Safer Alternatives
Learn Python percent-style %s formatting with strings, tuples, mappings, escaping percent signs, type conversions, and modern alternatives.