Using different clock sources with SoapySDR python

I am working on an application with the LimeSDR using the SoapySDR python bindings to apply DSP effects to an ~20MHz input signal. For this project, I would like to use the phase locked external clock as the sampling clock for the RX input using the SoapySDR python bindings. I have been able to get the LimeSDR to phase lock with an external clock using the LimeSuiteGUI.

I have the following code to get more information on the clocks before I start reading from the stream into the RX buffers.

    print("Master Clock Rate:", sdr.getMasterClockRate())
    print("Clock Source List:",sdr.listClockSources())
    print("Clock Source:",sdr.getClockSource())
    print("Time Source:",sdr.getTimeSource())

Here is the output:

Master Clock Rate: 299559997.55859375
Clock Source List: ()
Clock Source:
Time Source:

I am confused why it does not list any clock sources and why the external clock is not listed.

Would it be possible to use the SoapySDR function setClockSource() to set the phase locked external clock as the sampling clock or master clock?
What can I use as an argument to setClockSource() to have the clock source be the external clock?

Thank you,

Hopefully @Garmus may be able to advise and if not, would suggest posting in the Pothosware group.