Next Release Date for Economic series?

Hello. I was trying to get the next release date of an economic series through Datastream's python package, but failed to do so. I've looked for solutions on the internet, but also failed. In my opinion, the python package has a poor description: https://github.com/hoenie-ams/PyDSWS compared to its R fellow: https://github.com/CharlesCara/DatastreamDSWS2R

Anyway, I've looked for a solution in R and managed to find it. Here is my code:

>require(DatastreamDSWS2R)

>options(Datastream.Username = "XXXXXXX")

>options(Datastream.Password = "XXXXXXX")

>mydsws <- dsws$new()

>myData <- mydsws$listRequest(instrument = "USGDP...D",
datatype = "DS.NDOR1",
requestDate = "0D")

>myData

If you try the code above, you will get the ticker's next release date.

While in python...

>import PyDSWS

>ds = PyDSWS.Datastream(username='XXXXXXX', password='XXXXXXX')

>df = ds.get_data(tickers = 'USGDP...D, ', fields = 'DS.NDOR1')

>print(df)

it does not work.

I have also tried different combinations of DS.NDOR1, such as DS_NDOR1, NDOR_1, DSNDOR_1, but all failed. I don't know where I'm getting it wrong.

Is there a simple solution for that?