將文件前多少行或隔幾行讀取到另一個文件

n=0
with open('D:\AllData\cnews\\train.tsv',"r", encoding='UTF-8') as f:
    with open("train.tsv", "w", encoding='UTF-8') as f1:
     for line in f.readlines():
      n=n+1
      if n <15:
          f1.writelines(line)