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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 getCompoundIdForFeatureId(self, featureId):
 """ Returns server-style compound ID for an internal featureId. :param long featureId: id of feature in database :return: string representing ID for the specified GA4GH protocol Feature object in this FeatureSet. """

        if featureId is not None and featureId != "":
            compoundId = datamodel.FeatureCompoundId(
                self.getCompoundId(), str(featureId))
        else:
            compoundId = ""
        return str(compoundId)