def get_subtitle_download_url(response_content):
download_url = ""
parser = MyHTMLParser()
parser.feed(response_content)
for attr in parser.attrs:
attr_name, attr_value = attr
if attr_name == "src" and attr_value.find(SUBTITLE_PAGE) >= 0:
download_url = SUBTITLE_DOWNLOAD_URL % attr_value
break
parser.close()
return download_url
