Always use python2 runtime environment
Always use python2 runtime environment

Provide python2 environment for obvious-ci if necessary

cdeil/conda-builder-affiliated,astropy/conda-builder-affiliated,kbarbary/conda-builder-affiliated,astropy/conda-build-tools,Cadair/conda-builder-affiliated,Cadair/conda-builder-affiliated,mwcraig/conda-builder-affiliated,mwcraig/conda-builder-affiliated,bmorris3/conda-builder-affiliated,kbarbary/conda-builder-affiliated,astropy/conda-builder-affiliated,zblz/conda-builder-affiliated,cdeil/conda-builder-affiliated,zblz/conda-builder-affiliated,bmorris3/conda-builder-affiliated,astropy/conda-build-tools