explicit env in meta.yaml. sigh.

Author: Matthew Chan

.travis.yml

@@ -137,7 +137,6 @@ script:
 # Unit tests and dynamic linting
 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 - if [[ $TRAVIS_TAG ]]; then
-    export CONDA_PY=${MYCONDAPY//./};
     conda build -q tools/conda.recipe;
   else
     python setup.py build_ext -i --define CYTHON_TRACE_NOGIL &&

tools/conda.recipe/meta.yaml

@@ -13,7 +13,7 @@ requirements:
     - {{ compiler('c') }}
     - {{ compiler('cxx') }}
   host:
-    - python >=3
+    - python ={{ MYCONDAPY }}
     - libint 
     - cython >=0.24.1
     - numpy