Migrate from jax.core to jax.extend.core for several deprecated symbols

A number of symbols from jax.core are deprecated as of recent JAX releases; some of them are newly available in jax.extend.core.

PiperOrigin-RevId: 705932315

tf2jax/_src/ops.py

@@ -22,6 +22,7 @@
 
 import jax
 from jax.experimental import checkify
+import jax.extend as jex
 from jax.lib import xla_client
 import jax.numpy as jnp
 import numpy as np
@@ -2554,9 +2555,9 @@ def _func(x: jnp.ndarray) -> jnp.ndarray:
 
 
 def _maybe_get_jaxpreqn(
-    jaxpr: jax.core.ClosedJaxpr) -> Optional[jax.core.JaxprEqn]:
+    jaxpr: jex.core.ClosedJaxpr) -> Optional[jex.core.JaxprEqn]:
   def is_all_vars(vs):
-    return all([isinstance(v, jax.core.Var) for v in vs])
+    return all([isinstance(v, jex.core.Var) for v in vs])
 
   if (len(jaxpr.eqns) == 1 and
       is_all_vars(jaxpr.jaxpr.invars) and is_all_vars(jaxpr.jaxpr.outvars) and

tf2jax/experimental/mhlo.py

@@ -20,6 +20,7 @@
 import jax
 from jax import core
 from jax import export
+import jax.extend as jex
 from jax.interpreters import mlir
 from jax.interpreters import xla
 from jax.lib import xla_client as xc
@@ -31,7 +32,7 @@
 
 safe_zip = jax.util.safe_zip
 
-mhlo_apply_p = core.Primitive("mhlo_apply")
+mhlo_apply_p = jex.core.Primitive("mhlo_apply")
 mhlo_apply_p.multiple_results = True