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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 _description(self):
 """A concise html explanation of this Action."""


        inst = self.timemachine.presently

        if self.action_type == "dl":
            return "Deleted %s" % inst.content_type.name
        elif self.action_type == "cr":
            return "Created %s" % inst._object_type_html()
        else:
            return "Modified %s" % inst._object_type_html()