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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 get_versions(self):
 """ Returns a list of available versions for this item :return: list of versions :rtype: list[DriveItemVersion] """


        if not self.object_id:
            return []
        url = self.build_url(
            self._endpoints.get('versions').format(id=self.object_id))

        response = self.con.get(url)
        if not response:
            return []

        data = response.json()

        # Everything received from cloud must be passed as self._cloud_data_key
        return [DriveItemVersion(parent=self, **{self._cloud_data_key: item})
                for item in data.get('value', [])]