“python_requires” should be set with “>=3”, as cloudtracker 2.1.5 is not compatible with all Python versions.

[PyVCEchecker]

Currently, the keyword argument python_requires of setup() is not set, and thus it is assumed that this distribution is compatible with all Python versions.
However, I found it is not compatible with Python2. My local Python version is 2.7, and I encounter the following error when executing “pip install cloudtracker”

Collecting cloudtracker
  Using cached cloudtracker-2.1.5.tar.gz (80 kB)
    ERROR: Command errored out with exit status 1:
     command: /usr/local/bin/python -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-wbT82F/cloudtracker/setup.py'"'"'; __file__='"'"'/tmp/pip-install-wbT82F/cloudtracker/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-install-wbT82F/cloudtracker/pip-egg-info
         cwd: /tmp/pip-install-wbT82F/cloudtracker/
    Complete output (7 lines):
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-wbT82F/cloudtracker/setup.py", line 33, in <module>
        long_description=get_description(),
      File "/tmp/pip-install-wbT82F/cloudtracker/setup.py", line 22, in get_description
        return open(os.path.join(os.path.abspath(HERE), 'README.md'), encoding='utf-8').read()
    TypeError: 'encoding' is an invalid keyword argument for this function
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.

I found that setup.py used a Python3-specific keyword argument encoding for the function open, which lead to installation failure of cloudtracker in Python2.

Way to fix:
modify setup() in setup.py, add python_requires keyword argument:

setup(…
     python_requires='>=3',
     …)

Thanks for your attention.
Best regrads,
PyVCEchecker