code: def convert_concat(net, node, module, builder):
      
      # Get input and output names
      input_names, output_name = _get_input_output_name(net, node, 'all')
      name = node['name']
      mode = 'CONCAT'
      builder.add_elementwise(name = name, input_names = input_names,
              output_name = output_name, mode = mode)
docs: Convert concat layer from mxnet to coreml.
  
      Parameters
      ----------
      network: net
          A mxnet network object.
  
      layer: node
          Node to convert.
  
      module: module
          An module for MXNet
  
      builder: NeuralNetworkBuilder
          A neural network builder object.