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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 get_digest_by_class(self, current_class):
 """ Return the SHA256 hash of the object containing the ClassDefItem Returns the first digest this class was present. For example, if you analyzed an APK, this should return the digest of the APK and not of the DEX file. """

        for digest, dx in self.analyzed_vms.items():
            if dx.is_class_present(current_class.get_name()):
                return digest
        return None