Clearing a widget from session state?

I can’t seem to figure out how to clear a widget from session state after it is used either before the rerun on the subsequent rerun

On rerun, when I identify the widget key as truthy ala:
if “microphone_audio” in st.session_state:
st.session_state.microphone_audio = None

I try to set to None and get this error:

StreamlitValueAssignmentNotAllowedError: Values for the widget with key ‘microphone_audio’ cannot be set using st.session_state.

In this case I am using the st.experimental_audio_input widget in 1.39.0

UPDATE:

In case anyone else struggles with this, figured out it can be removed:
del st.session_state[“placeholder_for_widget_key”]