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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 delete_tree(self, key):
 """Delete all keys under given root key. Basic implementation works by just listing all available keys and deleting them individually but storage providers can implement more efficient logic."""

        self.log.debug("Deleting tree: %r", key)
        names = [item["name"] for item in self.list_path(key, with_metadata=False, deep=True)]
        for name in names:
            self.delete_key(name)