Explainer
Check whether a Python string contains a substring
Use in for substring checks, find or index for positions, and casefold for caseless matching. Avoid confusing a zero position with a failed search.
Explainer
Check for an empty or whitespace-only string in Python
Distinguish empty strings, whitespace, and None in Python, and choose an input check that matches the types your application accepts.
Explainer
Check whether a Python string represents a number
Choose integer, floating-point, or digit validation in Python. Handle signs, Unicode digits, NaN, infinity, and conversion errors explicitly.
Technical guide
Check out a remote Git branch
Fetch a remote branch and create a local tracking branch, resolve ambiguous remote names, or inspect the commit in detached HEAD.
Explainer
Clear or bypass an Nginx cache safely
Distinguish proxy and FastCGI caches from browser caches, understand bypass versus purge, and avoid a burst of origin traffic.
Technical guide
Clone a Git repository into a specific folder
Pass a destination directory to git clone, clone into an empty current folder, or connect an existing folder to a remote after preserving local files.
Explainer
Add color to Python logging output
Use colorlog or a custom logging formatter for terminal colors, while keeping redirected output and file logs free of ANSI escape sequences.
Explainer
Concatenate lists in Python
Choose list addition, unpacking, extend, or itertools.chain based on whether you need a new list, in-place changes, or lazy iteration.
Technical guide
Ignore local files in Git without changing the shared .gitignore
Use the repository exclude file or a global ignore file for personal untracked files. Understand why skip-worktree does not reliably ignore tracked edits.
Explainer
Convert an integer to a string in Python
Use str for integer conversion and f-strings for formatted text. Handle concatenation, padding, numeric bases, and conversion back to integers.
Explainer
Copy files and directory trees in Python
Use shutil.copy, copy2, and copytree, understand metadata limits and overwrites, and handle errors without treating a file copy as a complete backup.
Explainer
Pause execution in Python with sleep
Use time.sleep in synchronous code and asyncio.sleep in coroutines, with clear limits for timing accuracy, thread behavior, and recurring schedules.