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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 insert(self, identified):
 """ Inserts an already-created identified object of the expected class. """


        if not isinstance(identified, self._class):
            raise self.Error("Passed instance is not of the needed class",
                             self.Error.INVALID_INSTANCE_CLASS, instance=identified)

        try:
            if self._objects[identified.key] != identified:
                raise self.Error("Passes instance's key '%s' is already occupied" % identified.key,
                                 self.Error.KEY_EXISTS, key=identified.key, instance=identified)
        except KeyError:
            self._objects[identified.key] = identified
            self._events.insert.trigger(list=self, instance=identified)
        return identified