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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 preprocess(self):
        '''
        Performs initial cell conversions to standard types. This will strip units, scale numbers,
        and identify numeric data where it's convertible.
        '''
        self.processed_tables = []
        self.flags_by_table = []
        self.units_by_table = []
        for worksheet, rtable in enumerate(self.raw_tables):
            ptable, flags, units = self.preprocess_worksheet(rtable, worksheet)
            self.processed_tables.append(ptable)
            self.flags_by_table.append(flags)
            self.units_by_table.append(units)

        return self.processed_tables