def METHOD_NAME(self, url):
    """ Takes an URL and prepares it to be streamed. This function will try to unshorten the passed URL and, if needed, to transform it into a valid URL."""
    log.debug("Preparing URL: %s" % (url,))
    self.prepared = False
    self.url = url
    if self.url == None:
        self.url = url
        log.debug("Expanded URL: %s" % (self.url,))
    if self.url != None:
        transformer = audio_services.find_url_transformer(self.url)
        transformed_url = transformer(self.url)
        self.url = transformed_url
    log.debug("Transformed URL: %s. Prepared" % (self.url,))
    self.prepared = True