rental.py

class Rental(object):

    def __init__(self, customer, imdbID, pricer):
        self._customer = customer
        self._movie = pricer.price(imdbID)

    def __str__(self):
        return "Movie Rental - customer: " + self._customer \
               + ". Movie => title: " + self._movie.title \
               + ", price: £" + str(self._movie.price)

    def customer(self):
        return self._customer

    def movie_price(self):
        return self._movie.price()

    def movie_title(self):
        return self._movie.title()