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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 make_slash_number(self):
 """ Charset lines have \2 or \3 depending on type of partitioning and codon positions requested for our dataset. :return: """

        if self.partitioning == 'by codon position' and self.codon_positions == '1st-2nd':
            return '\\2'
        elif self.partitioning in ['by codon position', '1st-2nd, 3rd'] and self.codon_positions in ['ALL', None]:
            return '\\3'
        else:
            return ''