Install on Debian Bullseye fails due to python2 requirements

[sharbi]

Bug description:
Using most recent Raspbian Version 11 (Bullseye) the install fails during the line 56:

oref0/bin/openaps-install.sh

Line 56 in acb0150

apt-get -o Acquire::ForceIPv4=true update && apt-get -o Acquire::ForceIPv4=true install -y sudo strace tcpdump screen acpid vim python-pip locate ntpdate ntp

Throwing the error: E: Package 'python pip' has no installation candidate
Due to python2 being removed on this version of Raspbian.

To Reproduce
Steps to reproduce the behavior:

1. Flash bullseye to new SD card
2. Run usual installation process
3. See error

Expected behavior
Expected installation to complete or at least get through python installations

Setup Information (please complete the following information):

• Pump type: Medtronic 722
• CGM type: Libre with xDrip+
• Rig type: Pi Zero 2 running Raspbian Bullseye
• oref0 version: 0.62 master

Additional context
Is python2 required for installation? Or would it be possible just by updating the installation code to python3-pip?

Thanks!

[dcacklam]

Python2 is required for installation because most of the python in oref0 is python2
Python3-pip is installed later on (during oref0-setup) but this is of no use because we need python2 versions of the modules.

Prior to Bullseye, Debian did the 'smart' thing and assumed that references to 'python' meant Python 2 (meaning that if you want to use Python3 you had to #!/usr/bin/python3 (or similar).

Bullseye turned this on it's head and made Py3 the default, while removing py2 pip from the distro.

The 'fix' is 2-fold: install the python-is-python2 and python-dev-is-python2 packages, and manually install pip2 from pypa with curl.

A further change that is needed, is to add awareness of aarch64 to oref0-setup's go install routines, because 64bit Bullseye for raspberry pi is now a thing.

Also, because the install routine uses openaps-install.sh from master even-if you are installing DEV branch, this has to be patched in both branches for it to work when installing DEV.

Patches submitted to address this - #1428 (master) and #1429 (dev)