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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 locations_to_cache(locations, latest=False):
 """ Return a cumulative cache file build from the list of locations Parameters locations : list A list of strings containing files, globs, or cache files used to build a combined lal cache file object. latest : Optional, {False, Boolean} Only return a cache with the most recent frame in the locations. If false, all results are returned. Returns ------- cache : lal.Cache A cumulative lal cache object containing the files derived from the list of locations """

    cum_cache = lal.Cache()
    for source in locations:
        flist = glob.glob(source)
        if latest:
            def relaxed_getctime(fn):
                # when building a cache from a directory of temporary
                # low-latency frames, files might disappear between
                # the glob() and getctime() calls
                try:
                    return os.path.getctime(fn)
                except OSError:
                    return 0
            flist = [max(flist, key=relaxed_getctime)]

        for file_path in flist:
            dir_name, file_name = os.path.split(file_path)
            _, file_extension = os.path.splitext(file_name)

            if file_extension in [".lcf", ".cache"]:
                cache = lal.CacheImport(file_path)
            elif file_extension == ".gwf" or _is_gwf(file_path):
                cache = lalframe.FrOpen(str(dir_name), str(file_name)).cache
            else:
                raise TypeError("Invalid location name")

            cum_cache = lal.CacheMerge(cum_cache, cache)
    return cum_cache