Keras为此提供了一层AveragePooling1D.如果使用图谱API，则应该能够执行以下操作:

Keras has a layer AveragePooling1D for that. If you use the graph API, you should be able to do something like:

model.add_node(AveragePooling1D(...), 
               inputs=['h0', 'h1', ..., 'hn'], 
               merge_mode='concat', ...)