pathlib.Path

                Path(*segments)
              

Purpose

Path represents a filesystem path as an object with methods, replacing manual string concatenation (directory + "/" + filename) with something that works correctly on both Windows (\) and POSIX (/) path separators.

Example

from pathlib import Path

directory = Path("data")
config_path = directory / "config.json"        # Path('data/config.json')

config_path.write_text('{"ready": true}', encoding="utf-8")
text = config_path.read_text(encoding="utf-8")

print(config_path.name)    # "config.json"
print(config_path.suffix)  # ".json"
print(config_path.parent)  # Path('data')

Behavior notes

• The / operator joins path segments (directory / "config.json") — this is Path’s own operator overload, not filesystem division, and it produces the correct separator for whichever platform the code runs on.
• read_text()/write_text() (and their binary counterparts read_bytes()/write_bytes()) open the file, do the operation, and close it again, all in one call — no explicit with block needed for this common case, though a context manager is still what happens internally.
• Path objects are immutable — / and methods like .with_suffix(...) return a new Path rather than modifying the original, the same immutability shape str has.
• Always pass encoding="utf-8" explicitly for text methods rather than relying on the platform default encoding, which differs between operating systems and can silently produce different bytes for the same text.

Common mistakes

• Building paths with string concatenation or manual / characters ("data/" + filename) instead of Path — this breaks on Windows, where the native separator is \, and doesn’t normalize redundant separators or .. segments the way Path does.
• Omitting encoding="utf-8" and relying on the platform default — code that “works” during development can produce garbled output (or crash on genuinely non-ASCII text) once it runs somewhere with a different default encoding.

Implementation notes

Path’s cross-platform behavior — producing the correct separator and semantics for the running operating system — is a documented, language-guaranteed feature of the standard library, not a CPython-specific detail.