Add autoflake to pre-commit config

.pre-commit-config.yaml

@@ -34,6 +34,12 @@ repos:
     hooks:
       - id: black
 
+  # Removes unused imports.
+  - repo: https://github.com/PyCQA/autoflake
+    rev: v2.3.1
+    hooks:
+      - id: autoflake
+
   # Finds spelling issues in code.
   - repo: https://github.com/codespell-project/codespell
     rev: v2.3.0

pyrobosim/pyrobosim/utils/general.py

@@ -77,8 +77,6 @@ def get(self, category):
 class InvalidEntityCategoryException(Exception):
     """Raised when an invalid entity metadata category is used."""
 
-    pass
-
 
 def replace_special_yaml_tokens(in_text, root_dir=None):
     """

pyrobosim_ros/examples/demo_pddl_planner.py

@@ -143,7 +143,7 @@ def do_plan(self):
         try:
             result = self.world_state_future_response.result()
             update_world_from_state_msg(self.world, result.state)
-        except Exception as e:
+        except Exception:
             self.get_logger().info("Failed to unpack world state.")
 
         # Once the world state is set, plan using the first robot.