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Why should you use the logging module instead of print() for diagnostic output? What are Python's five standard logging severity levels, from lowest to highest? How do you format log output to include the timestamp, logger name, level, and message? What is the relationship between Logger, Handler, Formatter, and Filter in the logging module? Why is it recommended to use logging.getLogger(__name__) instead of the root logger in library and module code? How do you configure logging using a dictionary via logging.config.dictConfig? How do you include structured context (like a request ID) in every log message using LoggerAdapter or extra? What's the difference between propagate=True and propagate=False on a logger? What's the danger of using %-style, f-string, or .format() interpolation directly in a log call's message argument versus lazy % substitution? How do RotatingFileHandler and TimedRotatingFileHandler prevent log files from growing unbounded?
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What does logging.basicConfig() do, and what are its common pitfalls?

Beginner

Answer

basicConfig() configures the root logger with a default handler, formatter, and level in one call -- convenient for quick scripts. Its main pitfall is that it only has an effect the first time it's called (subsequent calls are ignored unless force=True), which confuses developers who call it in multiple places expecting it to reconfigure logging each time.
import logging

logging.basicConfig(level=logging.DEBUG, format='%(asctime)s - %(message)s')
logging.debug('This will show with the configured format')
Real-world example A script's second basicConfig() call with a different level silently has no effect because logging was already configured elsewhere, causing confusing debugging sessions.

Common follow-ups: How do you force reconfiguration with force=True?;Why shouldn't libraries call basicConfig at import time?

Logging;Modules & Packaging
All 15 Logging questions