The idea is to clear the output of the python REPL provided by pyscript, embedded in a website.
I have tried the regular ways used in the OS console (os.system("clear"), print("\033c") and similar), but they don't work.
I have not found anything in the documentation of the py-repl or py-terminal elements.
A possible approach is to implement a function in python that uses the js module provided by pyscript to modify the DOM (see How to perform DOM manipulation using pyscript).
So a simplified version of my solution would look like this:
<py-script>
from js import document as _DOC
def clear():
ter = _DOC.getElementById("my-terminal")
ter.innerHTML = ''
</py-script>
Put this code before your REPL and now you can execute the clear() function from it and the terminal will be cleared.