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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 __parse(self, string=''):
        '''
        Parse a string to remove and replace all wiki markup tags
        '''
        self.string = string
        self.string = self.wiki_re.sub('', self.string)
        # search for lists
        self.listmatch = re.search('^(\*+)', self.string)
        if self.listmatch:
            self.string = self.__list(self.listmatch) + re.sub('^(\*+)', \
                          '', self.string)
        return self.string