add compatibility with pyomo 5.7.0 (#172)

* add compatibility with pyomo 5.7.0

* add release notes [skip travis]

doc/release_notes.rst

@@ -13,6 +13,7 @@ Upcoming Release
 
 * Added an option to alter the capital cost of carriers by a factor via ``carrier+factor`` in the ``{opts}`` wildcard. This can be useful for exploring uncertain cost parameters. Example: ``solar+0.5`` reduces the capital cost of solar to 50% of original values (`#167 <https://github.com/PyPSA/pypsa-eur/pull/167>`_).
 
+* Add compatibility for pyomo 5.7.0 in :mod:`cluster_network` and :mod:`simplify_network`.
 
 PyPSA-Eur 0.2.0 (8th June 2020)
 ==================================

environment.docs.yaml

@@ -9,7 +9,7 @@ channels:
 dependencies:
   #- python
   - pip
-  - pypsa>=0.17 
+  - pypsa>=0.17.1
   - atlite=0.0.3
 
   # Dependencies of the workflow itself

environment.yaml

@@ -12,7 +12,7 @@ dependencies:
   - python
   - pip
 
-  - pypsa>=0.17 
+  - pypsa>=0.17.1
   - atlite=0.0.3
 
   # Dependencies of the workflow itself

scripts/cluster_network.py

@@ -221,7 +221,7 @@ def distribute_clusters(n, n_clusters, focus_weights=None, solver_name=None):
         opt = po.SolverFactory('ipopt')
 
     results = opt.solve(m)
-    assert results['Solver'][0]['Status'].key == 'ok', "Solver returned non-optimally: {}".format(results)
+    assert results['Solver'][0]['Status'] == 'ok', "Solver returned non-optimally: {}".format(results)
 
     return pd.Series(m.n.get_values(), index=L.index).astype(int)