Replace deprecated jax.tree_* functions with jax.tree.*

The top-level `jax.tree_*` aliases have long been deprecated, and will soon be removed. Alternate APIs are in `jax.tree_util`, with shorter aliases in the `jax.tree` submodule, added in JAX version 0.4.25.

PiperOrigin-RevId: 634149223

Author: Jake VanderPlas

trax/layers/research/efficient_attention_test.py

@@ -94,14 +94,14 @@ def _test_equivalence_to_reference_code(
       test_all = self._run_forward_and_backward(test_model, inp, weights, state)
       test_out, test_state, test_inp_grad, test_weights_grad = test_all
 
-      self.assertEqual(jax.tree_structure(ref_out),
-                       jax.tree_structure(test_out))
-      self.assertEqual(jax.tree_structure(ref_state),
-                       jax.tree_structure(test_state))
-      self.assertEqual(jax.tree_structure(ref_inp_grad),
-                       jax.tree_structure(test_inp_grad))
-      self.assertEqual(jax.tree_structure(ref_weights_grad),
-                       jax.tree_structure(test_weights_grad))
+      self.assertEqual(jax.tree.structure(ref_out),
+                       jax.tree.structure(test_out))
+      self.assertEqual(jax.tree.structure(ref_state),
+                       jax.tree.structure(test_state))
+      self.assertEqual(jax.tree.structure(ref_inp_grad),
+                       jax.tree.structure(test_inp_grad))
+      self.assertEqual(jax.tree.structure(ref_weights_grad),
+                       jax.tree.structure(test_weights_grad))
 
       check_close = lambda x, y: self.assertAllClose(x, y, rtol=2e-3, atol=2e-3)
       fastmath.nested_map_multiarg(check_close, ref_out, test_out)
@@ -168,7 +168,7 @@ def get_slice_for_val(x):
                                    dtype=x.dtype)
         else:
           return x[:, i:i+1]
-      return jax.tree_map(get_slice_for_val, pytree)
+      return jax.tree.map(get_slice_for_val, pytree)
 
     seqlen = x[0].shape[1] if isinstance(x, (tuple, list)) else x.shape[1]
 

trax/models/research/bert.py

@@ -308,9 +308,9 @@ def reshape_bias(name):
     for a, b in zip(fastmath.tree_leaves(self.weights), new_w):
       assert a.shape == b.shape, (
           f'Expected shape {a.shape}, got shape {b.shape}')
-    self.weights = jax.tree_unflatten(jax.tree_structure(self.weights), new_w)
+    self.weights = jax.tree.unflatten(jax.tree.structure(self.weights), new_w)
     move_to_device = jax.jit(lambda x: x)
-    self.weights = jax.tree_map(move_to_device, self.weights)
+    self.weights = jax.tree.map(move_to_device, self.weights)
 
   def _settable_attrs(self):
     """We allow to set attributes required for loading the model from its checkpoints."""