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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 create_filebase_name(self, group_info, extension='gz', file_name=None):
 """ Return tuple of resolved destination folder name and file name """

        dirname = self.filebase.formatted_dirname(groups=group_info)
        if not file_name:
            file_name = self.filebase.prefix_template + '.' + extension
        return dirname, file_name