Apply ruff/Perflint rule PERF403

PERF403 Use a dictionary comprehension instead of a for-loop

xarray/backends/memory.py

@@ -27,11 +27,7 @@ def get_variables(self):
         return self._variables
 
     def get_dimensions(self):
-        dims = {}
-        for v in self._variables.values():
-            for d, s in v.dims.items():
-                dims[d] = s
-        return dims
+        return {d: s for v in self._variables.values() for d, s in v.dims.items()}
 
     def prepare_variable(self, k, v, *args, **kwargs):
         new_var = Variable(v.dims, np.empty_like(v), v.attrs)

xarray/core/dataset.py

@@ -9364,10 +9364,11 @@ def pad(
         # keep indexes that won't be affected by pad and drop all other indexes
         xindexes = self.xindexes
         pad_dims = set(pad_width)
-        indexes = {}
-        for k, idx in xindexes.items():
-            if not pad_dims.intersection(xindexes.get_all_dims(k)):
-                indexes[k] = idx
+        indexes = {
+            k: idx
+            for k, idx in xindexes.items()
+            if not pad_dims.intersection(xindexes.get_all_dims(k))
+        }
 
         for name, var in self.variables.items():
             var_pad_width = {k: v for k, v in pad_width.items() if k in var.dims}