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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 split_by_extensions(filename):
 """ Splits the filename string by the extension of the file """

        parts = filename.split('.')
        idx = len(parts) - 1
        while FileFormat.is_file_format(parts[idx]):
            parts[idx] = FileFormat(parts[idx])
            idx -= 1
        return ['.'.join(parts[:idx + 1])] + parts[idx + 1:]