Install pip with Python 2 needs documentation update

[gitclem]

pip version

20.3.4

Python version

2.7.16

OS

Mac OS 10.15.7

Additional information

No response

Description

On page:
https://pip.pypa.io/en/stable/installing/

It says to install pip, use:

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py

This does not work on Python 2.7. You get the Python error:

python get-pip.py
Traceback (most recent call last):
File "get-pip.py", line 24244, in
main()
File "get-pip.py", line 199, in main
bootstrap(tmpdir=tmpdir)
File "get-pip.py", line 82, in bootstrap
from pip.internal.cli.main import main as pip_entry_point
File "/var/folders/k/blmzttsn5m35fd86smzys36h0000gp/T/tmpFuDDh2/pip.zip/pip/_internal/cli/main.py", line 60
sys.stderr.write(f"ERROR: {exc}")

The correct way to install pip on Python 2 is:

curl https://bootstrap.pypa.io/2.7/get-pip.py -o get-pip.py

and then
python get-pip.py

Expected behavior

pip for Python 2.7 should install without errors

How to Reproduce

1. curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
2. python get-pip.py # using python 2.7
3. An error occurs because python2.7 doesn't understand formatted strings of python 3.7: f""

Output

python get-pip.py
Traceback (most recent call last):
  File "get-pip.py", line 24244, in <module>
    main()
  File "get-pip.py", line 199, in main
    bootstrap(tmpdir=tmpdir)
  File "get-pip.py", line 82, in bootstrap
    from pip._internal.cli.main import main as pip_entry_point
  File "/var/folders/k_/blmzttsn5m35fd86smzys36h0000gp/T/tmpFuDDh2/pip.zip/pip/_internal/cli/main.py", line 60
    sys.stderr.write(f"ERROR: {exc}")

Code of Conduct

• I agree to follow the PSF Code of Conduct

Either the get-pip.py should be made to run with either version of Python OR the documentation ( https://pip.pypa.io/en/stable/installing/ ) needs updating.

[pfmoore]

https://pip.pypa.io/en/stable/installing/#python-and-os-compatibility

Pip no longer supports Python 2.

[gitclem]

https://pip.pypa.io/en/stable/installing/#python-and-os-compatibility

Pip no longer supports Python 2.

Well, the documentation should say that. But in any case what I did, does work, so that should be documented.

I do think it’s important to support 2.7 as much as possible because some OS tools still use 2.7 (eg the Mac). For my work, I’ve moved over to 3.x except I’m having an awful time with installing pylucene so I’m trying 2.7 and it’s almost working whereas 3.x dies in ways that I don’t understand.

[pradyunsg]

Well, the documentation should say that.

@pfmoore linked you to pip's documentation. Could you clarify what more you want the documentation to say?

Would a dedicated section talking about Python 2 support help? We have that too: https://pip.pypa.io/en/stable/development/release-process/#python-2-support

[gitclem]

Well, the documentation should say that.

@pfmoore linked you to pip's documentation. Could you clarify what more you want the documentation to say?

Would a dedicated section talking about Python 2 support help? We have that too: https://pip.pypa.io/en/stable/development/release-process/#python-2-support

I thought I made it clear. On page:
https://pip.pypa.io/en/stable/installing/

The paragraph entitled "Installing with get-pip.py" says:

To manually install pip, securely 1 download get-pip.py by following this link: get-pip.py. Alternatively, use curl:

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
Then run the following command in the folder where you have downloaded get-pip.py:
Unix/macOS
python get-pip.py

This section says nothing about this being for 3.x only. If you try to follow the instructions, you get an error about the 3.x python formatted string f"ERROR: {exc}"

I get that the world is moving away from 2.7 to 3.x. I'm using 3.x myself and get annoyed whenever I have to deal with 2.7

The problem is, a lot of old OS tools (e.g. on the Mac) depend on Python 2.7, and that's not going to get fixed any time soon.

Add extra disclaimers about 3.x or pointers to 2.7 pip would help a person not get lost in the weeds as to what was wrong.

[pradyunsg]

That page clearly states:

The get-pip.py script is supported on the same python version as pip.

We can probably remove the Python 2.6 link and have a better sentence to direct users to the right place tho.

[gitclem]

That page clearly states:

The get-pip.py script is supported on the same python version as pip.

We can probably remove the Python 2.6 link and have a better sentence to direct users to the right place tho.

Let me point out that other people have stumbled over this problem, so it's not just me who find the instructions not clear enough:

https://stackoverflow.com/questions/65866417/pip-install-failing-on-python2

[devilmen80]

Yes me too. But with this command pip2 will be installed and will not entry in conflict with pip3?

[gitclem]

Yes me too. But with this command pip2 will be installed and will not entry in conflict with pip3?

It shouldn't... On my mac:

which pip3
/usr/local/bin/pip3
which pip2
/usr/local/bin/pip2
which pip
/Users/user/Library/Python/2.7/bin/pip

On the other hand, my pip2 got mangled some how and it died because it had the formatted f"" python 3.x string. I just fixed it. And like I said, my Mac OS X 10.15.7 uses Python 2.7 for its system stuff. I use pyenv for my 3.8 work.

[pradyunsg]

This should be resolved by pypa/get-pip#100.