A recent push to the master branch now allows real-time SDR streaming from the RTL-SDR to pyaudio_helper.
This capability is made possible via the new asynch and await capabilities of Python 3.7. For the details as to how this works you have to dig into the details found in the module rtlsdr_helper.py and the examples found in the notebook rtlsdr_helper_streaming_sample.ipynb.
This is just the beginning of making a complete SDR receiver possible in a Jupyter notebook. Not only is the receiver a reality, the algorithms that implement the receiver, in Python, can easily be coded by the user.
To help develop demodulator algorithms a streaming code block interface standard, of sorts, is being developed this summer. The idea is to provide examples of how to write a simple Python class that will manage states in the DSP code that is inside the Callback Process block of the block diagram. More details by the end of the summer is expected, along with another sample notebook.