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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 app_to_object(self):
 """Return the application object encoded by the tag."""

        if self.tagClass != Tag.applicationTagClass:
            raise ValueError("application tag required")

        # get the class to build
        klass = self._app_tag_class[self.tagNumber]
        if not klass:
            return None

        # build an object, tell it to decode this tag, and return it
        return klass(self)