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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def make_layer_stack(layers=gin.REQUIRED, num_layers=6):
 """Configurable layer stack. Args: layers: a list of subclasses of TransformerLayer num_layers: an integer Returns: a LayerStack """

  return LayerStack([cls() for cls in layers] * num_layers)