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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 keep_types_s(s, types):
 """ Keep the given types from a string Same as :meth:`keep_types` but does not use the :attr:`params` dictionary Parameters s: str The string of the returns like section types: list of str The type identifiers to keep Returns ------- str The modified string `s` with only the descriptions of `types` """

        patt = '|'.join('(?<=\n)' + s + '\n(?s).+?\n(?=\S+|$)' for s in types)
        return ''.join(re.findall(patt, '\n' + s.strip() + '\n')).rstrip()