class_docstr: A trajectory of interactions with a RL environment.
  
  Trajectories are created when interacting with an RL environment. They can
  be prolonged and sliced and when completed, allow to re-calculate returns.
class_docstr_tok: ["A","trajectory","of","interactions","with","a","RL","environment",".","Trajectories","are","created","when","interacting","with","an","RL","environment",".","They","can","be","prolonged","and","sliced","and","when","completed",",","allow","to","re-calculate","returns","."]
docstr: Default way to convert timestep to numpy.
docstr_tok: ["Default","way","to","convert","timestep","to","numpy","."]
code: def _default_timestep_to_np(self, ts):
      """Default way to convert timestep to numpy."""
      return fastmath.nested_map(np.array, ts)
  
imports: import collections
  import os
  import gin
  import gym
  import numpy
  from trax import fastmath
  from trax.rl import advantages
  from trax.supervised import training
label_desc: Use image node_id 12 for calling the Trajectory obj's underlying member method code with example usage: obj._default_timestep_to_np(ts) and returns: fastmath