I'm trying to upgrade Python 3.7 to 3.9 on macOS Big Sur. I'm also trying to avoid losing packages that were installed on Python 3.7 and reinstalling them again on Python 3.9
I tried using
brew install python3
brew update && brew upgrade python
which yielded
Already up-to-date.
Warning: python3 3.9.1_7 already installed
However when I run python3 --version it yields Python 3.7.0
Is this an issue with the alias? Is there a way to uninstall Python 3.7 and keep Python 3.9?
Running brew link python3 yields
Linking /usr/local/Cellar/python#3.9/3.9.1_7...
Error: Could not symlink bin/2to3
Target /usr/local/bin/2to3
already exists. You may want to remove it:
rm '/usr/local/bin/2to3'
To force the link and overwrite all conflicting files:
brew link --overwrite python#3.9
To list all files that would be deleted:
brew link --overwrite --dry-run python#3.9
I fixed this frustrating error by first removing the Python 3.7 manually, by deleting it from the Applications folder and then uninstalling Python 3.9 using brew uninstall python3
Next, I downloaded and installed the latest Python from here and it worked!
To save all the installed packages by generating a requirements file, Run
python3 -m pip freeze > requirements.txt
and to install them in another environment, Run
python3 -m pip install -r requirements.txt
I suggest use official binaries:
Download version you need from the python.org
Call the .pkg
Invoke Update Shell Profile.command script under /Applications/Python\ 3.XX/
After all reboot your terminal
Check your Python version. The old version and dependencies remain intact.
Related
I'm trying to make a pip install of the fastf1 library. I noticed that I was using py 3.7 and that lib requires 3.8 or superior. I updated my interpreter (to python 3.10) but, the pip install keeps returning "ERROR: Could not find a version that satisfies the requirement fastf1". My python --version returns 3.10, but my pip version, although updated, still calling the anaconda's pip
How do I change the main pip to be used in this project?
Terminal result:
PS C:\Users...\Github\speedmetrica\DataAnalysis> python --version
Python 3.10.0
PS C:\Users...\Github\speedmetrica\DataAnalysis> pip --version
pip 21.3.1 from c:\users\jgbal\anaconda3\lib\site-packages\pip (python 3.7)
If python --version is running the desired version of Python, instead of running:
pip install packagename
run:
python -mpip install packagename
That runs the pip module installed for that version of Python as the entry point using the same Python executable you've been running, so it will install for that version of Python as well.
If you're on Windows, and installed as admin to install the Python launcher for Windows, you can be avoid relying on the PATH having a specific version appear first by running:
py -3 -mpip install packagename
which will run the latest installed version of Python 3. Changing to:
py -3.10 -mpip install packagename
will force it to run the latest installed copy of Python 3.10 specifically.
I have Python 3.8 and 3.9 installed via Homebrew:
~ brew list | grep python
python#3.8
python#3.9
I want to use Python 3.9 as my default one with python3 command. I tried the following:
~ brew switch python 3.9
Error: python does not have a version "3.9" in the Cellar.
python's installed versions: 3.8.6
I tried to uninstall Python and reinstall it, but it's used by other packages:
~ brew uninstall python
Error: Refusing to uninstall /usr/local/Cellar/python#3.8/3.8.6
because it is required by glib and php, which are currently installed.
You can override this and force removal with:
brew uninstall --ignore-dependencies python
How can I use Python 3.9?
There is an Homebrew known issue related to side by side install of Python 3.8 / 3.9. To workaround, following commands should work for you:
brew unlink python#3.9
brew unlink python#3.8
brew link --force python#3.9
Re-opening your terminal or execute command rehash can be required to take account the change.
Use pyenv. It's a software that lets you switch between any and all Python versions installed on your system. To install pyenv, use the following code in the command-line:
curl https://pyenv.run | bash
exec $SHELL
Then find the name of the python version you want to switch to with this:
pyenv versions
And select it with this:
pyenv global <version-name>
In your case, it's most likely named 3.9.0.
Updated MacOs Monterrey
For who are facing this problem add the pyenv path to your ~/.zshrc shell file.
export PATH="/Users/username/.pyenv/shims:${PATH}
eval "$(pyenv init --path)
Run in the terminal:
source ~/.zshrc
Check it out:
python3 --version
Font from the issue on GitHub.
i was working with python 3.7 and i installed recently python 3.8 in linux.
Is there any bash command or script that take a list of all packages of 3.7 and install it one by one in 3.8 version.
i want to avoid to do it by hand every package.
Note: i install them in my system not using venv.
Thanks!
/path_to_3.7_bin/python -m pip freeze > /home/packages_list.txt
then
/path_to_3.8_bin/python -m pip install -r /home/packages_list.txt
try https://pip.pypa.io/en/stable/reference/pip_freeze/
pip freeze > requirements.pip in the old version
pip install -r requirements.pip in the new version
I think I broke my pip after desperately trying to uninstall Python3.7. (I am on a Mac)
I removed the python folder from the application, removed /Library/Frameworks/Python.framework and removed the folders from /usr/local/bin according to https://osxuninstaller.com/uninstall-guides/properly-uninstall-python-mac/. I then installed python3.6.
src$ pip3.6 --version pip 9.0.1 from
/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages
(python 3.6)
but pip itself does no longer work.
src$ which pip
/usr/local/bin/pip
src$ pip --version
-bash: /Library/Frameworks/Python.framework/Versions/3.7/bin/pip: No such file or directory $
It still references the python 3.7 folder. How can I unlink that reference? THe same is btw. true for the package virtualenv that I installed. I can install it with pip3.6 but calling virtualenv still references to the framework folder of 3.7
You need to install pip in that environment. i.e 3.7.
Reason is when you deleted the default install you deleted the dependencies/ libraries that came with it.
Easiest way is to install python afresh via homebrew if you have it.
brew install python
Alternatively you can follow the instructions here to download a file to install pip securely. Homebrew can become messy when managing python environments. I'd recommend looking at something like anaconda if you are going to using different python versions with their own dependencies etc.
curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
python get-pip.py
https://pip.pypa.io/en/stable/installing/#installing-with-get-pip-py
Other options for fresh install are described in answer here. Hope that helps.
How do I install pip on macOS or OS X?
I am on shared hosting and I need to install pip with the correct python version, 2.7. To install pip, I did:
$ easy_install pip
However, after it was installed I get the following:
[dave#web1 lib]$ pip --version
pip 1.0.2 from /home/premiere/dave/financials/lib/pip-1.0.2-py2.7.egg (python 2.4)
How would I re-install pip to work on the python2.7 version, which is also installed on the machine?
[premiered#web1 ~]$ python --version
Python 2.6.6
Which is strange, since it is installing to python2.4.
You may want to create a virtualenv using -p /path/to/python-2.7.binary param, and then activate it. Then all stuff you installed using pip would be correctly into your virtualenv.
If multiple versions of python are installed on the system, then you should invoke the version you want when installing. i.e.
$ python27 easy_install pip
This creates a pip file in your path that contains the specified version of python in the hashBang line.