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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 extendMarkdown(self, md, md_globals):
 """ Add an instance of FigcaptionProcessor to BlockParser. """


        # def_list = 'def_list' in md.registeredExtensions
        md.parser.blockprocessors.add(
            'figcaption', FigcaptionProcessor(md.parser), '<ulist')