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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 maskQuality(self, umi, umi_quals):
        '''mask low quality bases and return masked umi'''
        masked_umi = mask_umi(umi, umi_quals,
                              self.quality_encoding,
                              self.quality_filter_mask)
        if masked_umi != umi:
            self.read_counts['UMI masked'] += 1
            return masked_umi
        else:
            return umi