o cleanup code make it more readable

Author: rajeeja

uxarray/core/utils.py

@@ -28,20 +28,21 @@ def _open_dataset_with_fallback(filename_or_obj, chunks=None, **kwargs):
     xr.Dataset
         The opened dataset
     """
+    # First attempt: use xarray's default read engine
+    original_error = None
     try:
-        # Try opening with xarray's default read engine
         return xr.open_dataset(filename_or_obj, chunks=chunks, **kwargs)
-    except Exception as first_error:
-        # If it fails, try with the "netcdf4" engine as backup
+    except Exception as e:
+        original_error = e
+
+    # Second attempt: fallback to netcdf4 engine
+    try:
         # Extract engine from kwargs to prevent duplicate parameter error
         engine = kwargs.pop("engine", "netcdf4")
-        try:
-            return xr.open_dataset(
-                filename_or_obj, engine=engine, chunks=chunks, **kwargs
-            )
-        except Exception:
-            # If both attempts fail, raise the original error to preserve the original behavior
-            raise first_error
+        return xr.open_dataset(filename_or_obj, engine=engine, chunks=chunks, **kwargs)
+    except Exception:
+        # If both attempts fail, raise the original error to preserve behavior
+        raise original_error
 
 
 def _map_dims_to_ugrid(