def open_assets_marker?
      return false if !op_return_data_only_script?
      data = op_return_data
      return false if !data || data.bytesize < 6
      if data[0, AssetMarker::PREFIX_V1.bytesize] == AssetMarker::PREFIX_V1
        return true
      end
      false
    end
def open_assets_marker?
      return false if !op_return_data_only_script?
      data = op_return_data
      return false if !data || data.bytesize < 6
      if data[0, AssetMarker::PREFIX_V1.bytesize] == AssetMarker::PREFIX_V1
        return true
      end
      false
    end
Returns `true` if this script may be a valid OpenAssets marker.
 Only checks the prefix and minimal length, does not validate the content.
 Use this method to quickly filter out non-asset transactions.