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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_hosts(self, pattern):
 """ finds hosts that postively match a particular pattern. Does not take into account negative matches. """


        (name, enumeration_details) = self._enumeration_info(pattern)
        hpat = self._hosts_in_unenumerated_pattern(name)
        hpat = sorted(hpat, key=lambda x: x.name)

        return set(self._apply_ranges(pattern, hpat))