pip fails to install ruamel.yaml.clib with error "minimum python version(s): [(3, 5)]"

[php-coder]

$ trap 'travis_terminate 1' ERR; if [ "$SPRING_PROFILES_ACTIVE" = 'travis' ]; then mysql -u root -e 'CREATE DATABASE mystamps CHARACTER SET utf8;'; mkdir -p /tmp/uploads /tmp/preview; cp src/main/resources/test/test.png /tmp/uploads/1.png; npm install -g [email protected]; pip install --user html5validator==0.3.3 robotframework-lint==1.1 ansible==2.9.2 ansible-lint==4.2.0; if [ "$TRAVIS_PULL_REQUEST" != 'false' ]; then gem install danger:8.2.2 nokogiri:1.10.10 --no-document; fi; sudo apt-get -qq update; sudo apt-get install -y shellcheck; elif [ "$SPRING_PROFILES_ACTIVE" = 'postgres' ]; then psql -U postgres -c 'create database mystamps;'; fi
/home/travis/.nvm/versions/node/v8.12.0/bin/bootlint -> /home/travis/.nvm/versions/node/v8.12.0/lib/node_modules/bootlint/src/cli-main.js
+ [email protected]
added 51 packages from 22 contributors in 3.189s
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/__init__.py:83: RequestsDependencyWarning: Old version of cryptography ([1, 2, 3]) may cause slowdown.
  warnings.warn(warning, RequestsDependencyWarning)
DEPRECATION: Python 2.7 reached the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 is no longer maintained. pip 21.0 will drop support for Python 2.7 in January 2021. More details about Python 2 support in pip, can be found at https://pip.pypa.io/en/latest/development/release-process/#python-2-support
Collecting html5validator==0.3.3
  Downloading html5validator-0.3.3.tar.gz (25.5 MB)
Collecting robotframework-lint==1.1
  Downloading robotframework-lint-1.1.tar.gz (23 kB)
Collecting ansible==2.9.2
  Downloading ansible-2.9.2.tar.gz (14.2 MB)
Collecting ansible-lint==4.2.0
  Downloading ansible_lint-4.2.0-py2.py3-none-any.whl (57 kB)
Collecting robotframework
  Downloading robotframework-4.0.3-py2.py3-none-any.whl (655 kB)
Collecting jinja2
  Downloading Jinja2-2.11.3-py2.py3-none-any.whl (125 kB)
Requirement already satisfied: PyYAML in /usr/lib/python2.7/dist-packages (from ansible==2.9.2) (3.11)
Requirement already satisfied: cryptography in /usr/lib/python2.7/dist-packages (from ansible==2.9.2) (1.2.3)
Requirement already satisfied: six in /usr/lib/python2.7/dist-packages (from ansible-lint==4.2.0) (1.10.0)
Collecting ruamel.yaml<1,>=0.15.34; python_version < "3.7"
  Downloading ruamel.yaml-0.16.13-py2.py3-none-any.whl (111 kB)
Collecting pathlib2; python_version < "3.2"
  Using cached pathlib2-2.3.5-py2.py3-none-any.whl (18 kB)
Collecting MarkupSafe>=0.23
  Downloading MarkupSafe-1.1.1-cp27-cp27mu-manylinux1_x86_64.whl (24 kB)
Collecting ruamel.ordereddict; platform_python_implementation == "CPython" and python_version <= "2.7"
  Downloading ruamel.ordereddict-0.4.15-cp27-cp27mu-manylinux1_x86_64.whl (93 kB)
Collecting ruamel.yaml.clib>=0.1.2; platform_python_implementation == "CPython" and python_version < "3.10"
  Downloading ruamel.yaml.clib-0.2.4.tar.gz (180 kB)
    ERROR: Command errored out with exit status 1:
     command: /usr/bin/python -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-Mg44QL/ruamel.yaml.clib/setup.py'"'"'; __file__='"'"'/tmp/pip-install-Mg44QL/ruamel.yaml.clib/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-pip-egg-info-PZQ8D7
         cwd: /tmp/pip-install-Mg44QL/ruamel.yaml.clib/
    Complete output (1 lines):
    minimum python version(s): [(3, 5)]
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.

It seems like robotframework-lint pulls newest robotframework 4.0.3 that pulls on ruamel.yaml.clib 0.2.4 that requires Python 3.5 We had the similar situation in #1404

Here is the logs: https://travis-ci.com/github/php-coder/mystamps/jobs/520956003

[php-coder]

Everything worked before with robotframework 3.2.2 and ruamel.yaml.clib 0.2.2:

Collecting ruamel.ordereddict; platform_python_implementation == "CPython" and python_version <= "2.7"
  Downloading ruamel.ordereddict-0.4.15-cp27-cp27mu-manylinux1_x86_64.whl (93 kB)
Collecting ruamel.yaml.clib>=0.1.2; platform_python_implementation == "CPython" and python_version < "3.9"
  Downloading ruamel.yaml.clib-0.2.2-cp27-cp27mu-manylinux1_x86_64.whl (493 kB)