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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 find_obj_by_tag(self, tag):
 """Search through all the objects in the world and return the first instance whose tag matches the specified string."""

        for obj in self.__up_objects:
            if obj.tag == tag:
                return obj

        for obj in self.__draw_objects:
            if obj.tag == tag:
                return obj

        return None