Python3 repl missing readline?

Hi all. I've just installed python3-light onto a fresh (lantiq) router which has an up-to-date snapshot on it. When I run the python3 repl on my other debian linux boxes, the cursor keys let me navigate through the command history, but when I use the cursor keys on this python3 installation, I get what appear to be control characters echoed to the screen instead of history navigation, thus:

# python
Python 3.9.2 (default, Feb 27 2021, 18:14:27) 
[GCC 8.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> help
Type help() for interactive help, or help(object) for help about object.
>>> ^[[A # This is what appears after pressing "cursor up"

I believe that this is due to a problem between python and the readline library (although I am not sure of this). Does anyone know whether this is easily fixable?

TIA, Jaime

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