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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 merge(file, feature_layers):
    ''' Retrieve a list of OSciMap4 tile responses and merge them into one.

        get_tiles() retrieves data and performs basic integrity checks.
    '''
    tile = VectorTile(extents)

    for layer in feature_layers:
        tile.addFeatures(layer['features'], layer['name'])

    tile.complete()

    data = tile.out.SerializeToString()
    file.write(struct.pack(">I", len(data)))
    file.write(data)