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* Handle empty `href` and `content` attribute values (`22 <https://github.com/scottwernervt/favicon/issues/22>`_).
* Support passing request library parameters to `favicon.get()` (`21 <https://github.com/scottwernervt/favicon/issues/21>`_).
* Deprecate `headers` argument. Use keyword arguments: `favicon.get(url, headers={'User-Agent'; 'my-agent'}`.