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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 sort_replies(self, thats=False):
 """Sort the loaded triggers in memory. After you have finished loading your RiveScript code, call this method to populate the various internal sort buffers. This is absolutely necessary for reply matching to work efficiently! """

        # (Re)initialize the sort cache.
        self._sorted["topics"] = {}
        self._sorted["thats"]  = {}
        self._say("Sorting triggers...")

        # Loop through all the topics.
        for topic in self._topics.keys():
            self._say("Analyzing topic " + topic)

            # Collect a list of all the triggers we're going to worry about.
            # If this topic inherits another topic, we need to recursively add
            # those to the list as well.
            alltrig = inherit_utils.get_topic_triggers(self, topic, False)

            # Sort them.
            self._sorted["topics"][topic] = sorting.sort_trigger_set(alltrig, True, self._say)

            # Get all of the %Previous triggers for this topic.
            that_triggers = inherit_utils.get_topic_triggers(self, topic, True)

            # And sort them, too.
            self._sorted["thats"][topic] = sorting.sort_trigger_set(that_triggers, False, self._say)

        # And sort the substitution lists.
        if not "lists" in self._sorted:
            self._sorted["lists"] = {}
        self._sorted["lists"]["sub"] = sorting.sort_list(self._sub.keys())
        self._sorted["lists"]["person"] = sorting.sort_list(self._person.keys())