Installing pip is not working in python < 3.6

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 3.6 install from https://bootstrap.pypa.io/pip/3.6/
• For Python 3.5 install from https://bootstrap.pypa.io/pip/3.5/
• For Python 3.4 install from https://bootstrap.pypa.io/pip/3.4/
• For Python 3.4 the upgrade command is

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