code: def pbroadcast(x, named_axis=None):
      axes = canonicalize_named_axis(named_axis)
      for axis in axes:
          x = rwb_pbroadcast(x, axis)
      return x
  
imports: import collections
  import functools
  import tensorflow.compat.v2
  from tensorflow_probability.python.internal import custom_gradient
  from tensorflow_probability.python.internal import prefer_static
  from tensorflow_probability.python.internal import samplers
  from tensorflow.python.util import nest
label_desc: Use image node_id 4 for calling a global function with example usage: pbroadcast(x, named_axis) and returns: x