class_docstr: Step size adaptation state.
code: def step_size(self, num_adaptation_steps=None):
      if num_adaptation_steps is not None:
          return jnp.where(
              self.step < num_adaptation_steps,
              self.opt_step_size(),
              self.rms_step_size,
          )
      else:
          return self.opt_step_size()
  
imports: import functools
  import typing
  from typing import Any, Callable, Iterable, NamedTuple, Optional
  import numpy
  from fun_mc import backend
  from fun_mc import fun_mc_lib
  from fun_mc import malt
  from fun_mc import sga_hmc
  from fun_mc.malt import *
  from fun_mc.sga_hmc import *
label_desc: Use image node_id 3 for calling the StepSizeAdaptationState obj's underlying member method code with example usage: obj.step_size(num_adaptation_steps) and returns: jnp, self