大文件的简单文件分割

# -*- coding:utf-8 -*-
from datetime import datetime
 
def Main():
    source_dir = '/jz_yuanshi_list0206.txt'
    target_dir = '/split/'
 
    # 计数器
    flag = 0
 
    # 文件名
    name = 1
 
    # 存放数据
    dataList = []
 
    print("开始。。。。。")
    print(datetime.now().strftime('%Y-%m-%d %H:%M:%S'))
 
    with open(source_dir,'r') as f_source:
        for line in f_source:
          flag+=1
          dataList.append(line)
          if flag == 2000000:
              with open(target_dir+"jz_yuanshi_list_"+str(name)+".txt",'w+') as f_target:
                  for data in dataList:
                      f_target.write(data)
              name+=1
              flag = 0
              dataList = []
                
    # 处理最后一批行数少于200万行的
    with open(target_dir+"jz_yuanshi_list_"+str(name)+".txt",'w+') as f_target:
        for data in dataList:
            f_target.write(data)
 
    print("完成。。。。。")
    print(datetime.now().strftime('%Y-%m-%d %H:%M:%S'))
 
if __name__ == "__main__":
    Main()