refactor: add require_package calls for grpcio and gym-hil in relevant modules

pyproject.toml

@@ -332,6 +332,9 @@ ignore = [
 "__init__.py" = ["F401", "F403", "E402"]
 # E402: conditional-import guards (TYPE_CHECKING / is_package_available) must precede the imports they protect
 "src/lerobot/scripts/convert_dataset_v21_to_v30.py" = ["E402"]
+"src/lerobot/rl/actor.py" = ["E402"]
+"src/lerobot/rl/learner.py" = ["E402"]
+"src/lerobot/rl/learner_service.py" = ["E402"]
 "src/lerobot/policies/wall_x/**" = ["N801", "N812", "SIM102", "SIM108", "SIM210", "SIM211", "B006", "B007", "SIM118"] # Supprese these as they are coming from original Qwen2_5_vl code TODO(pepijn): refactor original
 
 [tool.ruff.lint.isort]

src/lerobot/rl/actor.py

@@ -53,6 +53,10 @@ from functools import lru_cache
 from queue import Empty
 from typing import Any
 
+from lerobot.utils.import_utils import require_package
+
+require_package("grpcio", extra="hilserl", import_name="grpc")
+
 import grpc
 import torch
 from torch import nn

src/lerobot/rl/gym_manipulator.py

@@ -312,6 +312,9 @@ def make_robot_env(cfg: HILSerlRobotEnvConfig) -> tuple[gym.Env, Any]:
     # Check if this is a GymHIL simulation environment
     if cfg.name == "gym_hil":
         assert cfg.robot is None and cfg.teleop is None, "GymHIL environment does not support robot or teleop"
+        from lerobot.utils.import_utils import require_package
+
+        require_package("gym-hil", extra="hilserl", import_name="gym_hil")
         import gym_hil  # noqa: F401
 
         # Extract gripper settings with defaults

src/lerobot/rl/learner.py

@@ -53,6 +53,10 @@ from pathlib import Path
 from pprint import pformat
 from typing import Any
 
+from lerobot.utils.import_utils import require_package
+
+require_package("grpcio", extra="hilserl", import_name="grpc")
+
 import grpc
 import torch
 from termcolor import colored

src/lerobot/rl/learner_service.py

@@ -19,6 +19,10 @@ import logging
 import time
 from multiprocessing import Event, Queue
 
+from lerobot.utils.import_utils import require_package
+
+require_package("grpcio", extra="hilserl", import_name="grpc")
+
 from lerobot.transport import services_pb2, services_pb2_grpc
 from lerobot.transport.utils import receive_bytes_in_chunks, send_bytes_in_chunks