old_contents: from keras.layers import Convolution2D, Merge
  from keras.layers.advanced_activations import PReLU
  from keras.engine.topology import merge
  
  from eva.layers.masked_convolution2d import MaskedConvolution2D
  
  def ResidualBlock(model, filters):
      # 2h -> h
      block = Convolution2D(filters//2, 1, 1)(model)
      block = PReLU()(block)
  
      # h 3x3 -> h
      block = MaskedConvolution2D(filters//2, 3, 3, border_mode='same')(block)
      block = PReLU()(block)
  
      # h -> 2h
      block = Convolution2D(filters, 1, 1)(block)
  
      return PReLU()(merge([model, block], mode='sum'))
  
  def ResidualBlockList(model, filters, length):
      for _ in range(length):
          model = ResidualBlock(model, filters)
  
      return model
  
new_contents: from keras.layers import Convolution2D, Merge
  from keras.layers.advanced_activations import PReLU
  
  from eva.layers.masked_convolution2d import MaskedConvolution2D
  
  def ResidualBlock(model, filters):
      # 2h -> h
      block = PReLU()(model)
      block = MaskedConvolution2D(filters//2, 1, 1)(block)
  
      # h 3x3 -> h
      block = PReLU()(block)
      block = MaskedConvolution2D(filters//2, 3, 3, border_mode='same')(block)
  
      # h -> 2h
      block = PReLU()(block)
      block = MaskedConvolution2D(filters, 1, 1)(block)
  
      return Merge(mode='sum')([model, block])
  
  def ResidualBlockList(model, filters, length):
      for _ in range(length):
          model = ResidualBlock(model, filters)
  
      return model
  
subject: Fix residual blocks to be on-par with paper.