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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 copy(self, object_version=None, key=None):
 """Copy a tag to a given object version. :param object_version: The object version instance to copy the tag to. Default: current object version. :param key: Key of destination tag. Default: current tag key. :return: The copied object version tag. """

        return ObjectVersionTag.create(
            self.object_version if object_version is None else object_version,
            key or self.key,
            self.value
        )