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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 get_extended_summary(self, s, base=None):
 """Get the extended summary from a docstring This here is the extended summary Parameters s: str The docstring to use base: str or None A key under which the summary shall be stored in the :attr:`params` attribute. If not None, the summary will be stored in ``base + '.summary_ext'``. Otherwise, it will not be stored at all Returns ------- str The extracted extended summary"""

        # Remove the summary and dedent
        s = self._remove_summary(s)
        ret = ''
        if not self._all_sections_patt.match(s):
            m = self._extended_summary_patt.match(s)
            if m is not None:
                ret = m.group().strip()
        if base is not None:
            self.params[base + '.summary_ext'] = ret
        return ret