add reasoning_gym.create_dataset({name}, ...) global factory function

reasoning_gym/arithmetic/leg_counting.py

@@ -4,7 +4,7 @@ from dataclasses import dataclass
 from random import Random
 from typing import Dict, Optional
 
-from ..dataset import ProceduralDataset
+from ..factory import ProceduralDataset, register_dataset
 
 ANIMALS = {
     # Animals with 0 legs
@@ -115,19 +115,4 @@ class LegCountingDataset(ProceduralDataset):
         }
 
 
-def leg_counting_dataset(
-    min_animals: int = 2,
-    max_animals: int = 5,
-    max_instances: int = 3,
-    seed: Optional[int] = None,
-    size: int = 500,
-) -> LegCountingDataset:
-    """Create a LegCountingDataset with the given configuration."""
-    config = LegCountingConfig(
-        min_animals=min_animals,
-        max_animals=max_animals,
-        max_instances=max_instances,
-        seed=seed,
-        size=size,
-    )
-    return LegCountingDataset(config)
+register_dataset("leg_counting", LegCountingDataset, LegCountingConfig)