Use Ray _BackwardsCompatibleNumpyRng if possible (#421)

flaml/tune/sample.py

@@ -35,46 +35,48 @@ except AttributeError:
 
 logger = logging.getLogger(__name__)
 
+try:
+    from ray.tune.sample import _BackwardsCompatibleNumpyRng
+except ImportError:
+    class _BackwardsCompatibleNumpyRng:
+        """Thin wrapper to ensure backwards compatibility between
+        new and old numpy randomness generators.
+        """
 
-class _BackwardsCompatibleNumpyRng:
-    """Thin wrapper to ensure backwards compatibility between
-    new and old numpy randomness generators.
-    """
+        _rng = None
 
-    _rng = None
-
-    def __init__(
-        self,
-        generator_or_seed: Optional[
-            Union["np_random_generator", np.random.RandomState, int]
-        ] = None,
-    ):
-        if generator_or_seed is None or isinstance(
-            generator_or_seed, (np.random.RandomState, np_random_generator)
+        def __init__(
+            self,
+            generator_or_seed: Optional[
+                Union["np_random_generator", np.random.RandomState, int]
+            ] = None,
         ):
-            self._rng = generator_or_seed
-        elif LEGACY_RNG:
-            self._rng = np.random.RandomState(generator_or_seed)
-        else:
-            self._rng = np.random.default_rng(generator_or_seed)
+            if generator_or_seed is None or isinstance(
+                generator_or_seed, (np.random.RandomState, np_random_generator)
+            ):
+                self._rng = generator_or_seed
+            elif LEGACY_RNG:
+                self._rng = np.random.RandomState(generator_or_seed)
+            else:
+                self._rng = np.random.default_rng(generator_or_seed)
 
-    @property
-    def legacy_rng(self) -> bool:
-        return not isinstance(self._rng, np_random_generator)
+        @property
+        def legacy_rng(self) -> bool:
+            return not isinstance(self._rng, np_random_generator)
 
-    @property
-    def rng(self):
-        # don't set self._rng to np.random to avoid picking issues
-        return self._rng if self._rng is not None else np.random
+        @property
+        def rng(self):
+            # don't set self._rng to np.random to avoid picking issues
+            return self._rng if self._rng is not None else np.random
 
-    def __getattr__(self, name: str) -> Any:
-        # https://numpy.org/doc/stable/reference/random/new-or-different.html
-        if self.legacy_rng:
-            if name == "integers":
-                name = "randint"
-            elif name == "random":
-                name = "rand"
-        return getattr(self.rng, name)
+        def __getattr__(self, name: str) -> Any:
+            # https://numpy.org/doc/stable/reference/random/new-or-different.html
+            if self.legacy_rng:
+                if name == "integers":
+                    name = "randint"
+                elif name == "random":
+                    name = "rand"
+            return getattr(self.rng, name)
 
 
 RandomState = Union[