'Initialize the UberEstimate object.'

def __init__(self, session, start_latitude, start_longitude, end_latitude=None, end_longitude=None):

    self._session = session
    self.start_latitude = start_latitude
    self.start_longitude = start_longitude
    self.end_latitude = end_latitude
    self.end_longitude = end_longitude
    self.products = None
    self.update()
