code: def mean_absolute_error(y_true, y_pred):
      result = mean(abs(y_true - y_pred), axis=1)
      return result
  
imports: from bigdl.dllib.nncontext import *
  from bigdl.dllib.keras.autograd import *
  from bigdl.dllib.keras.layers import *
  from bigdl.dllib.keras.models import *
  from optparse import OptionParser
  import sys
  from bigdl.dllib.utils.log4Error import *
label_desc: Use image node_id 1 for calling a global function with example usage: mean_absolute_error(y_true, y_pred) and returns: result