import re
obj = re.search(r'@CAD_DTA\\">(.+?)@G@H@CAD_LBL', 'Some text here...@CAD_DTA\\">I WANT THIS@G@H@CAD_LBL')
print obj.start(1)
print obj.group(1)
aW1wb3J0IHJlCm9iaiA9IHJlLnNlYXJjaChyJ0BDQURfRFRBXFwiPiguKz8pQEdASEBDQURfTEJMJywgJ1NvbWUgdGV4dCBoZXJlLi4uQENBRF9EVEFcXCI+SSBXQU5UIFRISVNAR0BIQENBRF9MQkwnKQpwcmludCBvYmouc3RhcnQoMSkKcHJpbnQgb2JqLmdyb3VwKDEpCg==