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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 getVariantId(self, gaVariant):
 """ Returns an ID string suitable for the specified GA Variant object in this variant set. """

        md5 = self.hashVariant(gaVariant)
        compoundId = datamodel.VariantCompoundId(
            self.getCompoundId(), gaVariant.reference_name,
            str(gaVariant.start), md5)
        return str(compoundId)