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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, lines):
        '''Parse the lines.'''
        if self.type == 'msdos':
            return self.parse_msdos(lines)
        elif self.type == 'unix':
            return self.parse_unix(lines)
        elif self.type == 'nlst':
            return self.parse_nlst(lines)
        else:
            raise UnknownListingError('Unsupported listing type.')