code: def del_metadata_keys(self, bucket, label, keys):
          '''Delete the metadata corresponding to the specified keys.
          '''
          if self.mode !="r":
              try:
                  payload = self._get_bucket_md(bucket)
              except OFSFileNotFound:
                  # No MD found...
                  raise OFSFileNotFound("Couldn't find a md file for %s bucket" % bucket)
              except OFSException as e:
                  raise OFSException(e)
              if payload.has_key(label):
                  for key in [x for x in keys if payload[label].has_key(x)]:
                      del payload[label][key]
              self.put_stream(bucket, MD_FILE, json.dumps(payload), params={}, replace=True, add_md=False)
          else:
              raise OFSException("Cannot update MD in archive in 'r' mode"f del_metadata_keys(self, bucket, label, keys):
          '''Delete the metadata corresponding to the specified keys.
          '''
          if self.mode !="r":
              try:
                  payload = self._get_bucket_md(bucket)
              except OFSFileNotFound:
                  # No MD found...
                  raise OFSFileNotFound("Couldn't find a md file for %s bucket" % bucket)
              except OFSException as e:
                  raise OFSException(e)
              if payload.has_key(label):
                  for key in [x for x in keys if payload[label].has_key(x)]:
                      del payload[label][key]
              self.put_stream(bucket, MD_FILE, json.dumps(payload), params={}, replace=True, add_md=False)
          else:
              raise OFSException("Cannot update MD in archive in 'r' mode")
docs: Delete the metadata corresponding to the specified keys.