code: def mean_per_vertex_error(pred, gt, has_smpl):
      """
      Compute mPVE
      """
      pred = pred[has_smpl == 1]
      gt = gt[has_smpl == 1]
      with paddle.no_grad():
          error = paddle.sqrt(((pred - gt) ** 2).sum(axis=-1)).mean()
          return error
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from itertools import cycle, islice
  from collections import abc
  import paddle
  import paddle.nn
  import paddle.nn.functional
  from ppdet.core.workspace import register, serializable
  from ppdet.utils.logger import setup_logger
label_desc: Use image node_id 9 for calling a global function with example usage: mean_per_vertex_error(pred, gt, has_smpl) and returns: error