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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 _format_keyword(self, keyword):
 """ Removing special character from a keyword. Analysis Services must have this kind of keywords. E.g. if assay name from GeneXpert Instrument is 'Ebola RUO', an AS must be created on Bika with the keyword 'EbolaRUO' """

        import re
        result = ''
        if keyword:
            result = re.sub(r"\W", "", keyword)
            # Remove underscores ('_') too.
            result = re.sub(r"_", "", result)
        return result