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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):
 """ Every extension requires a extendMarkdown method to tell the markdown renderer how use the extension. """

        md.registerExtension(self)

        for processor in (self.preprocessors or []):
            md.preprocessors.add(processor.__name__.lower(), processor(md), '_end')

        for pattern in (self.inlinepatterns or []):
            md.inlinePatterns.add(pattern.__name__.lower(), pattern(md), '_end')

        for processor in (self.postprocessors or []):
            md.postprocessors.add(processor.__name__.lower(), processor(md), '_end')