is_available checks centralized

src/lerobot/motors/dynamixel/dynamixel.py

@@ -23,7 +23,7 @@ from copy import deepcopy
 from enum import Enum
 from typing import TYPE_CHECKING
 
-from lerobot.utils.import_utils import is_package_available, require_package
+from lerobot.utils.import_utils import _dynamixel_sdk_available, require_package
 
 from ..encoding_utils import decode_twos_complement, encode_twos_complement
 from ..motors_bus import Motor, MotorCalibration, NameOrID, SerialMotorsBus, Value, get_address
@@ -36,8 +36,6 @@ from .tables import (
     MODEL_RESOLUTION,
 )
 
-_dynamixel_sdk_available = is_package_available("dynamixel-sdk", import_name="dynamixel_sdk")
-
 if TYPE_CHECKING or _dynamixel_sdk_available:
     import dynamixel_sdk as dxl
 else:

src/lerobot/motors/feetech/feetech.py

@@ -18,7 +18,7 @@ from enum import Enum
 from pprint import pformat
 from typing import TYPE_CHECKING
 
-from lerobot.utils.import_utils import is_package_available, require_package
+from lerobot.utils.import_utils import _feetech_sdk_available, require_package
 
 from ..encoding_utils import decode_sign_magnitude, encode_sign_magnitude
 from ..motors_bus import Motor, MotorCalibration, NameOrID, SerialMotorsBus, Value, get_address
@@ -35,8 +35,6 @@ from .tables import (
     SCAN_BAUDRATES,
 )
 
-_feetech_sdk_available = is_package_available("feetech-servo-sdk", import_name="scservo_sdk")
-
 if TYPE_CHECKING or _feetech_sdk_available:
     import scservo_sdk as scs
 else:

src/lerobot/policies/groot/action_head/cross_attention_dit.py

@@ -20,9 +20,7 @@ import torch
 import torch.nn.functional as F  # noqa: N812
 from torch import nn
 
-from lerobot.utils.import_utils import is_package_available, require_package
+from lerobot.utils.import_utils import _diffusers_available, require_package
-
-_diffusers_available = is_package_available("diffusers")
 
 if TYPE_CHECKING or _diffusers_available:
     from diffusers import ConfigMixin, ModelMixin

src/lerobot/policies/wall_x/modeling_wall_x.py

@@ -52,8 +52,9 @@ from torch.nn import CrossEntropyLoss
 from lerobot.utils.constants import ACTION, OBS_STATE
 from lerobot.utils.import_utils import (
     _peft_available,
+    _qwen_vl_utils_available,
+    _torchdiffeq_available,
     _transformers_available,
-    is_package_available,
     require_package,
 )
 
@@ -71,8 +72,6 @@ from .constant import (
     TOKENIZER_MAX_LENGTH,
 )
 
-_torchdiffeq_available = is_package_available("torchdiffeq")
-_qwen_vl_utils_available = is_package_available("qwen-vl-utils", import_name="qwen_vl_utils")
 _wallx_deps_available = (
     _transformers_available and _peft_available and _torchdiffeq_available and _qwen_vl_utils_available
 )

src/lerobot/teleoperators/keyboard/teleop_keyboard.py

@@ -23,7 +23,7 @@ from typing import Any
 
 from lerobot.types import RobotAction
 from lerobot.utils.decorators import check_if_already_connected, check_if_not_connected
-from lerobot.utils.import_utils import is_package_available
+from lerobot.utils.import_utils import _pynput_available
 
 from ..teleoperator import Teleoperator
 from ..utils import TeleopEvents
@@ -33,7 +33,7 @@ from .configuration_keyboard import (
     KeyboardTeleopConfig,
 )
 
-PYNPUT_AVAILABLE = is_package_available("pynput")
+PYNPUT_AVAILABLE = _pynput_available
 keyboard = None
 if PYNPUT_AVAILABLE:
     try:

src/lerobot/utils/import_utils.py

@@ -95,13 +95,29 @@ def require_package(pkg_name: str, extra: str, import_name: str | None = None) -
         )
 
 
+# ── Centralised availability flags ────────────────────────────────────────
+# Every optional-dependency check lives here so that the rest of the codebase
+# can simply ``from lerobot.utils.import_utils import _foo_available``.
+# Do NOT define ad-hoc ``is_package_available(...)`` calls in other modules.
+
+# ML / training
 _transformers_available = is_package_available("transformers")
 _peft_available = is_package_available("peft")
 _scipy_available = is_package_available("scipy")
+_diffusers_available = is_package_available("diffusers")
+_torchdiffeq_available = is_package_available("torchdiffeq")
+
+# Hardware SDKs
+_dynamixel_sdk_available = is_package_available("dynamixel-sdk", import_name="dynamixel_sdk")
+_feetech_sdk_available = is_package_available("feetech-servo-sdk", import_name="scservo_sdk")
 _reachy2_sdk_available = is_package_available("reachy2_sdk")
 _can_available = is_package_available("python-can", "can")
 _unitree_sdk_available = is_package_available("unitree-sdk2py", "unitree_sdk2py")
+
+# Misc
+_pynput_available = is_package_available("pynput")
 _pygame_available = is_package_available("pygame")
+_qwen_vl_utils_available = is_package_available("qwen-vl-utils", import_name="qwen_vl_utils")
 
 
 def make_device_from_device_class(config: ChoiceRegistry) -> Any: