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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 _checkMetadata(self, variantFile):
 """ Checks that metadata is consistent """

        metadata = self._getMetadataFromVcf(variantFile)
        if self._metadata is not None and self._metadata != metadata:
            raise exceptions.InconsistentMetaDataException(
                variantFile.filename)