code: public AttributeInfoEx[] get_attribute_info_ex(final DeviceProxy deviceProxy) throws DevFailed {
  
          build_connection(deviceProxy);
  
          final String[] attributeNames = new String[1];
          if (deviceProxy.device_3 != null) {
              attributeNames[0] = TangoConst.Tango_AllAttr_3;
          } else {
              attributeNames[0] = TangoConst.Tango_AllAttr;
          }
  
          return get_attribute_info_ex(deviceProxy, attributeNames);
      }
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