Fix Black Missing Packaging Dependency | Generated by AI

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Question: Why does running python -m black scripts fail with “ModuleNotFoundError: No module named ‘packaging’” even though black is installed?

Answer:

The error occurs because the black package is installed, but one of its dependencies — the packaging library — is missing in your current Python environment.

This is the most common situation when:

• black was installed with --no-deps (intentionally or by some tool/script)
• the environment was partially corrupted / cleaned
• black was installed via some unusual method (e.g. python -m pip install --no-deps black)
• you are using a very new Python version (like Python 3.14 in your case) and some system/site-packages state became inconsistent
• you have multiple Python installations and black is in one but dependencies are missing in the interpreter you’re actually using

Quick fix (recommended)

# Reinstall black + all its dependencies
python -m pip install --force-reinstall black

# or the even cleaner version:
python -m pip uninstall black -y
python -m pip install black

Most people solve the problem with one of these two commands.

Alternative fixes

1. Install the missing package manually (quick & dirty)

python -m pip install packaging

→ then try python -m black scripts again

1. If you suspect environment confusion / wrong python

# Check which python & pip you're actually using
which python
which pip
python --version
pip --version

# Make sure they match, otherwise use the full path:
python3.14 -m pip install --force-reinstall black

1. If you’re in a virtual environment but forgot to activate it

source .venv/bin/activate          # macOS/Linux
# or
.\.venv\Scripts\activate           # Windows

then run python -m pip install black again.

Summary – most likely causes & solutions

Situation	Most likely fix
Missing dependency	pip install packaging or reinstall black
Corrupted / incomplete install	pip install --force-reinstall black
Wrong Python interpreter	Use python3.14 -m pip install black
Virtualenv not activated	Activate venv first
Installed with --no-deps	Reinstall without that flag

In 95% of cases on macOS/homebrew + recent Python, just running

python -m pip install --force-reinstall black

resolves the issue.

Try that first and let me know if it still fails.

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