code: def on_cpu(x):
      """Puts ``x`` in CPU memory in JAX."""
      if fastmath.is_backend(fastmath.Backend.JAX):
          return jax.device_put(x, jax.local_devices(backend="cpu")[0])
      else:
          return x
  
imports: import jax
  import numpy
  from trax import fastmath
  from trax.fastmath import numpy
  from trax.layers import base
label_desc: Use image node_id 7 for calling a global function with example usage: on_cpu(x) and returns: jax, x