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.
Tutorials
Browse Python tutorials for beginners and working developers, including syntax, libraries, examples, projects, and real problem-solving guides.
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.
Sort a Dictionary by Key in Python with sorted()
Sort a Python dictionary by key with sorted() and dict(), while making reverse order, case normalization, dates, and nested keys explicit.
Python %d Formatting: Integer Placeholders and Modern Alternatives
Use Python %d formatting for integers, width, zero padding, multiple values, and percent signs, then compare it with f-strings.
Python Ternary Operator: Conditional Expressions Clearly
Use Python ternary expressions for compact conditional values, avoid nested unreadable logic, and choose a normal if statement when the branches do more than return a value.
Python Serial Read with pySerial: Bytes, Lines, and Timeouts
Read reliable serial messages with pySerial by defining framing, timeout, buffering, byte decoding, disconnect, and cleanup behavior.