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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_html_desc(self, markdown_inst=None):
 """ Translates the enum's 'desc' property into HTML. Any RDLFormatCode tags used in the description are converted to HTML. The text is also fed through a Markdown processor. The additional Markdown processing allows designers the choice to use a more modern lightweight markup language as an alternative to SystemRDL's "RDLFormatCode". Parameters markdown_inst: ``markdown.Markdown`` Override the class instance of the Markdown processor. See the `Markdown module <https://python-markdown.github.io/reference/#Markdown>`_ for more details. Returns ------- str or None HTML formatted string. If node does not have a description, returns ``None`` """

        desc_str = self._rdl_desc_
        if desc_str is None:
            return None
        return rdlformatcode.rdlfc_to_html(desc_str, md=markdown_inst)