data = """ park 800905-1049118 kim 700905-1059119 """ result = [] for line in data.split("\n"): word_result = [] for word in line.split(" "): if len(word) == 14 and word[:6].isdigit() and word[7:].isdigit(): word = word[:6] + "-" + "*******" word_result.append(word) result.append(" ".join(word_result)) print("\n".join(result))