pip/python: normal site-packages is not writeable

Question

I have a new Macbook - a user installed it, and then I installed a new user (mine), granted admin privileges and deleted the old one. I am on OS Catalina.

Since the installation I've been having several permission problems. VSCode can't find Jupyter Notebook, pip installs packages at ~/Library/Python/3.7/site-packages.

When I do which python3 I get usr/bin/python3. When I do pip3 install <package> I get: Defaulting to user installation because normal site-packages is not writeable And then it says it has already been installed, even though I can't access it when I do import <package>.

It's seems clear that this is a permission problem, pip can't install to the "base" python, and them python can't find what I've installed into ~/Library/Python/3.7/site-packages.

I've tried reinstalling the OS, but since I haven't done a clean install, it didn't change anything. What am I missing? How exactly can I fix permissions? Where do I want packages to be installed (venv sure, but some packages I want global (like jupyter).

Answer 1

As @TomdeGeus mentioned in the comments, this command works for me:

Python 3:

python3 -m pip install [package_name]

Python 2:

python -m pip install [package_name]

Answer 2

It's best to not use the system-provided Python directly. Leave that one alone since the OS can change it in undesired ways, as you experienced.

The best practice is to configure your own Python version(s) and manage them on a per-project basis using virtualenv (for Python 2) or venv (for Python 3). This eliminates all dependency on the system-provided Python version, and also isolates each project from other projects on the machine.

Each project can have a different Python point version if needed, and gets its own site_packages directory so pip-installed libraries can also have different versions by project. This approach is a major problem-avoider.

Answer 3

python3.7 -m pip install [package_name]

(you should use the version that you have, of course)

solved it for me.

The most voted answer python3 -m pip install [package_name] does not help me here.

In my case, this was caused by a conflict with the dominating 3.6 version that was also installed as a default. You might ask yourself why you have 3.6 on your system, you will most probably not use that version now. The reason is that 3.6 is used as an independent default python version for many package installers. Those installers do not want to check which individual version you use and whether that fits, they just use 3.6 as a default, if you like it or not.

Here is a proof by example --upgrade pip:

pip3 install --upgrade pip

Defaulting to user installation because normal site-packages is not writeable
Requirement already satisfied: pip in /home/USERNAME/.local/lib/python3.6/site-packages (20.3.1)

python3 -m pip install --upgrade pip

Defaulting to user installation because normal site-packages is not writeable
Requirement already satisfied: pip in /home/USERNAME/.local/lib/python3.6/site-packages (20.3.1)

python3.7 -m pip install --upgrade pip

Collecting pip
Cache entry deserialization failed, entry ignored
Using cached https://files.pythonhosted.org/packages/ab/11/2dc62c5263d9eb322f2f028f7b56cd9d096bb8988fcf82d65fa2e4057afe/pip-20.3.1-py2.py3-none-any.whl
Installing collected packages: pip Successfully installed pip-20.3.1

Answer 4

It occurs with me when I the virtual enviroment folder name was : venv.

in this case, It gives errors like :

No module pip

Default folder is unwritable

renaming the folder solve the proplem.

Answer 5

Had this same issue on a fresh install of Debian 9.12. Rebooting my server solved the issue.

Answer 6

in my case python3 -m pip install [package_name] did not solve that. in my case, it was a problem related to other processes occupying the directory. I restart Pycharm and close any other program that might occupy this folder, and reinstalled the package in site-packages directory successfully.

Answer 7

I'm using Anaconda on Ubuntu and had the same problem.I fixed it by the following steps:

deactivating current environment

conda deactivate

Then, the base environment activates. I deactivated the base conda environment too. To do so, I used conda deactivate again.

Finally, I activate my project environment directly (instead of activating from the base environment) by the following command. Afterward, I installed the intended package successfully and worked perfectly.

conda activate myenv
pip install somepackage

Answer 8

When this problem occurred to me I have tried all the mentioned approaches but they don't seem to work.

Instead, restarting Python language server in my VSCode did the job - my SimPy package is now found. On Mac it is Cmd+Shift+P and select "Python: Restart Language Server".