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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 sample_string(self, individual=-1):
 """Returns the VCF entry as it appears in the vcf file"""

        base = str(self)
        extra = self.get_sample_info(individual=individual)
        extra = [':'.join([str(j) for j in i]) for i in zip(*extra.values())]
        return '\t'.join([base, '\t'.join(extra)])