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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 export_hmaps_csv(key, dest, sitemesh, array, comment):
 """ Export the hazard maps of the given realization into CSV. :param key: output_type and export_type :param dest: name of the exported file :param sitemesh: site collection :param array: a composite array of dtype hmap_dt :param comment: comment to use as header of the exported CSV file """

    curves = util.compose_arrays(sitemesh, array)
    writers.write_csv(dest, curves, comment=comment)
    return [dest]