SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
This is already provided in the base class, which performs the same
exact behavior. Given the function in the base class isn't virtual, this
also essentially resolves an instance of shadowing.
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