old_contents: import encoder
  import decoder
  
  # coordindates are scaled to this range within tile
  extents = 4096
  
  def decode(tile):
      vector_tile = decoder.TileData(extents)
      message = vector_tile.getMessage(tile)
      return message
  
  def encode(layers):
      ''' Retrieve a list of GeoJSON tile responses and merge them into one.
      
          get_tiles() retrieves data and performs basic integrity checks.
      '''
      vector_tile = encoder.VectorTile(extents)
      if (isinstance(layers, list)):
          for layer in layers:
              vector_tile.addFeatures(layer['features'], layer['name'])
      else:
          vector_tile.addFeatures(layers['features'], layers['name'])
  
      return vector_tile.tile.SerializeToString()
new_contents: import encoder
  import decoder
  
  # coordindates are scaled to this range within tile
  extents = 4096
  
  def decode(tile):
      vector_tile = decoder.TileData(extents)
      message = vector_tile.getMessage(tile)
      return message
  
  def encode(layers):
      vector_tile = encoder.VectorTile(extents)
      if (isinstance(layers, list)):
          for layer in layers:
              vector_tile.addFeatures(layer['features'], layer['name'])
      else:
          vector_tile.addFeatures(layers['features'], layers['name'])
  
      return vector_tile.tile.SerializeToString()
subject: remove comments that make no sense