Python shutil.copytree() Function: Usage and Examples

This Python tutorial explains shutil.copytree() Function: Usage and Examples. Follow the example, inspect the output, and practise an input change so you understand the behavior rather than simply copying the syntax.

What This Feature Does

Duplicate an entire directory tree with shutil.copytree().

shutil.copytree(source, destination, dirs_exist_ok=False) recursively copies a directory hierarchy. The destination must normally not exist; dirs_exist_ok=True allows merging into an existing tree, potentially overwriting files.

When to Use It

This technique belongs to file copying, temporary files and matching. It is useful when the input, operation and expected outcome are known. Start with a small controlled example before integrating it into a larger workflow.

Step-by-Step Python Example

Read the code once before running it. Notice which values are inputs, which function or method performs the work, and whether the result is returned or stored by changing an existing object.

from pathlib import Path
from tempfile import TemporaryDirectory
import shutil

with TemporaryDirectory() as temporary_folder:
    root_folder = Path(temporary_folder)
    source_folder = root_folder / "source"
    source_folder.mkdir()
    (source_folder / "config.json").write_text("{}", encoding="utf-8")
    destination_folder = shutil.copytree(source_folder, root_folder / "backup")
    print((destination_folder / "config.json").exists())

Understanding the Code

• First, the imports make pathlib, tempfile, shutil available. They provide the filesystem, data or standard-library functions used later.
• Find the call shutil.copytree(source_folder, root_folder / "backup"). Its parameters determine the specific operation demonstrated in the title.
• Its purpose is to duplicate an entire directory tree with shutil.copytree(). Compare this description against the result printed by the program.
• The sample uses TemporaryDirectory() so any practice files are removed after the context ends; it does not work on your real documents.
• The print() expressions display a checkable outcome. Print values and exception names are not substitutes for the program result itself.

Expected Output

True

The output is the observable result of the sample operation. Compare its value and type with the explanation, not just whether the program runs.

Important Details and Edge Cases

Review ignore patterns and permission handling before copying large trees.

Before applying this to real documents, check whether the method reads data, creates a new file, moves it, or overwrites an existing file. Work in a disposable test directory first and handle OSError-related failures in applications.

Practice: Try It Yourself

Copy a nested temporary folder into a fresh backup directory.

Begin by copying the example into a separate practice file. Change one input at a time, run it again, and describe why the result changed. If the exercise writes or deletes files, keep it inside a temporary test folder.

Official Python Documentation

For the complete reference, see the Python standard library documentation.

Common Beginner Mistakes

• Assuming an existing destination directory is accepted without dirs_exist_ok=True.
• Following symlinks without deciding whether to copy links or their targets.
• Before applying this to real documents, check whether the method reads data, creates a new file, moves it, or overwrites an existing file. Work in a disposable test directory first and handle OSError-related failures in applications.

Key Takeaways

• Duplicate an entire directory tree with shutil.copytree().
• shutil.copytree(source, destination, dirs_exist_ok=False) recursively copies a directory hierarchy. The destination must normally not exist; dirs_exist_ok=True allows merging into an existing tree, potentially overwriting files.
• Avoid this common pitfall: Assuming an existing destination directory is accepted without dirs_exist_ok=True.