ASE dropped python2 support (#265)

azure/install_dependencies.sh

@@ -2,4 +2,5 @@
 
 python -m pip install --upgrade pip
 pip install torch_nightly -f https://download.pytorch.org/whl/nightly/cpu/torch_nightly.html
-pip install tqdm ase pyyaml future
+pip install tqdm pyyaml future
+pip install 'ase<=3.17'
\ No newline at end of file

azure/install_dependencies_python2.sh

+#!/bin/bash
+
+python -m pip install --upgrade pip
+pip install torch_nightly -f https://download.pytorch.org/whl/nightly/cpu/torch_nightly.html
+pip install tqdm pyyaml future
+pip2 install 'ase<=3.17'
\ No newline at end of file

azure/python2.yml

@@ -19,7 +19,7 @@ steps:
   inputs:
     versionSpec: '$(python.version)'
 
-- script: 'azure/install_dependencies.sh && pip install .'
+- script: 'azure/install_dependencies_python2.sh && pip install .'
   displayName: 'Install dependencies'
 
 - script: 'python2 examples/energy_force.py'