Installing pip is not working in python < 3.6

Question

I am starting to make a app using bitbucket CI and i am using the following steps to deploy the application and the steps to install pip is failing.

 script:     - apt-get update     - apt-get install -y python-dev     - curl -O https://bootstrap.pypa.io/get-pip.py     - python get-pip.py     ... and a few more steps 

Dont know why but python get-pip.py step fails with the following error.

Traceback (most recent call last):   File "get-pip.py", line 24226, 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 "/tmp/tmpUgc5ng/pip.zip/pip/_internal/cli/main.py", line 60     sys.stderr.write(f"ERROR: {exc}")                                    ^  SyntaxError: invalid syntax  

This worked fine upto yesterday. Not sure why this is not working now.

I thought it may be because of windows but i checked in my local machine running linux but these steps but they worked fine.

Answer 1

pip 21.0 dropped support for Python 2 and 3.5. The later versions require Python 3.6+. The syntax f"" is supported by Python 3.6+.

To install pip for Python 2.7 install it from https://bootstrap.pypa.io/pip/2.7/ :

- curl -O https://bootstrap.pypa.io/pip/2.7/get-pip.py - python get-pip.py - python -m pip install --upgrade "pip < 21.0" 

The last command is to upgrade to the latest supported version. For Python 2.7 the latest supported is currently pip 20.3.4.

For Python 3.4 install from https://bootstrap.pypa.io/pip/3.4/ . For Python 3.5 — https://bootstrap.pypa.io/pip/3.5/ .

For Python 3.4 the upgrade command is

- python -m pip install --upgrade "pip < 19.2"