I need to help about House exercise, please!

Hi, I have doubts like it make the house exercise. I don’t understand like begin and use the parameters. for example, when I finish of iteration or it need a logical or sintaxis to build the new phrases. Any can I help me, please?

def recite(start_verse, end_verse):
    """ start_verse: frase inicial o frase a incrustar.
    end_verse: frase final con incrutsacion.
    if "{frase}" not in start_verse:
        return start_verse
    """ Incrustar la frase dentro de la frase principal. """
    start_verse = start_verse.replace("{frase}", end_verse)
    """ Llamar recursivamente a la función con la frase incrustada como frase principal. """
    return recite(start_verse, end_verse)

this is my code ago, where {frase} is the initial word to embed

Maybe this question should be done at the programming category here.