code: def diff(x, prepend=None):
      """Like jnp.diff."""
      return jnp.diff(x, prepend=prepend)
  
imports: import functools
  import jax
  from jax import lax
  from jax import random
  from jax import tree_util
  import jax.numpy
label_desc: Use image node_id 21 for calling a global function with example usage: diff(x, prepend) and returns: jnp