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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 _creation_options_for_cog(creation_options, source_profile, blocksize):
 """ it uses the profile of the source raster, override anything using the creation_options and guarantees we will have tiled raster and blocksize """

    if not(creation_options):
        creation_options = {}

    creation_options["blocksize"] = blocksize
    creation_options["tiled"] = True
    defaults = {"nodata": None, "compress": "lzw"}
    for key in ["nodata", "compress"]:
        if key not in creation_options:
            creation_options[key] = source_profile.get(key, defaults.get(key))
    return creation_options