Python文本解析

分片

分片，通过分片，记录偏移处，然后提取想要的字符串

line='aaa bbb ccc'  
col1=line[0:3]  
col3=line[8:]  
col1  
 #'aaa'  
col3  
# 'ccc'  

split()方法

line='aaa bbb ccc'  
   a=line.split (' ')  
   a  
   ['aaa', 'bbb', 'ccc']  
   a[0]  
  'aaa'  
   a[1]  
  'bbb'  
   a[2]  
  'ccc'  
   line='aaa,bbb,ccc'  
   a=line.split (',')  
   a  
  ['aaa', 'bbb', 'ccc']