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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 add_reads(self, reads):
 """ Create another VariantSequence with more supporting reads. """

        if len(reads) == 0:
            return self
        new_reads = self.reads.union(reads)
        if len(new_reads) > len(self.reads):
            return VariantSequence(
                prefix=self.prefix,
                alt=self.alt,
                suffix=self.suffix,
                reads=new_reads)
        else:
            return self