code: def _coord_grid_to_mesh_grid(coord_grid):
      if len(coord_grid) == 1:
          return tf.expand_dims(coord_grid[0], -1)
      return tf.stack(
          values=tf.meshgrid(*coord_grid, indexing="ij"), axis=-1
      )
  
imports: import tensorflow.compat.v2
  from tf_quant_finance import utils
  from tf_quant_finance.math import piecewise
  from tf_quant_finance.math.pde import fd_solvers
  from tf_quant_finance.models import ito_process
  from tf_quant_finance.models import utils
label_desc: Use image node_id 2 for calling a global function with example usage: _coord_grid_to_mesh_grid(coord_grid) and returns: tf, tf