refactor: use ternary if/else assignment for n_storage

powersimdata/input/scenario_grid.py

@@ -42,10 +42,7 @@ def _read_network(self):
         try:
             # The next line will fail if no iess attribute (index energy storage system)
             # Since we use the 'squeeze_me' param, 1 storage -> an int, not an array
-            if isinstance(mpc.iess, int):
-                n_storage = 1
-            else:
-                n_storage = mpc.iess.shape[0]
+            n_storage = 1 if isinstance(mpc.iess, int) else mpc.iess.shape[0]
         except AttributeError:
             n_storage = 0