Clean single-source support for Python 3 and 2
copied from cf-staging / futureconda install conda-forge::future
conda install conda-forge/label/broken::future
conda install conda-forge/label/cf201901::future
conda install conda-forge/label/cf202003::future
conda install conda-forge/label/gcc7::future
Python-future is the missing compatibility layer between Python 2 and Python 3. It allows you to use a single, clean Python 3.x-compatible codebase to support both Python 2 and Python 3 with minimal overhead.