code: def flat_concat(xs):
      return tf.concat([tf.reshape(x, (-1,)) for x in xs], axis=0)
  
file_path: spinningup/spinup/utils/mpi_tf.py
imports: import numpy
  import tensorflow
  from mpi4py import MPI
  from spinup.utils.mpi_tools import broadcast
label_desc: Use image node_id 1 for calling a global function with example usage: flat_concat(xs) and returns: tf