def prepare(self):
result_files = self.collect_files()<EOL>chain = self.prepare_handlers_chain<EOL>if chain is None:<EOL><INDENT>chain = [<EOL>LessCompilerPrepareHandler()<EOL>]<EOL><DEDENT>for prepare_handler in chain:<EOL><INDENT>result_files = prepare_handler.prepare(result_files, self)<EOL><DEDENT>return result_files<EOL>
Called when builder run collect files in builder group

:rtype: list[static_bundle.files.StaticFileResult]