can't install pip because python2.7 has no zlib support

can't install pip because python2.7 has no zlib support

root@XX:~# python2 get-pip.py
Traceback (most recent call last):
  File "get-pip.py", line 23974, 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
zipimport.ZipImportError: can't decompress data; zlib not available

root@XX:~# apt install zlib1g-dev
zlib1g-dev is already the newest version (1:1.2.11.dfsg-2ubuntu7).

ProblemType: Bug
DistroRelease: Ubuntu 21.10
Package: python2.7 2.7.18-8build1
ProcVersionSignature: Ubuntu 5.13.0-35.40-generic 5.13.19
Uname: Linux 5.13.0-35-generic x86_64
ApportVersion: 2.20.11-0ubuntu71
Architecture: amd64
CasperMD5CheckResult: pass
Date: Mon Mar 14 12:12:22 2022
InstallationDate: Installed on 2021-03-20 (359 days ago)
InstallationMedia: Ubuntu-Server 20.10 "Groovy Gorilla" - Release amd64 (20201022)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: python2.7
UpgradeStatus: Upgraded to impish on 2022-02-12 (30 days ago)