python file

 >>> help(open)
 Help on built-in function open in module __builtin__:

 open(...)
     open(name[, mode[, buffering]]) -> file object

     Open a file using the file() type, returns a file object.  This is the
     preferred way to open a file.  See file.__doc__ for further information.

 >>> f=open('E:\\tmp.txt')
 >>> f
 <open file 'E:\\tmp.txt', mode 'r' at 0x0000000002F84540>
 >>> f.read()
 'nihao\nwozhidao\n\xc4\xb2\xb0\xd8\xd0\xf1\n'
 >>> list(f)
 []
 >>> f.read(5)
 ''
 >>> f.read()
 ''
 >>> f=open("E:\\tmp.txt")
 >>> f.read
 <built-in method read of file object at 0x0000000002F845D0>
 >>> f.read()
 'nihao\nwozhidao\n\xc4\xb2\xb0\xd8\xd0\xf1\n'
 >>> f.read()
 ''
 >>> f=open("E:\\tmp.txt")
 >>> f
 <open file 'E:\\tmp.txt', mode 'r' at 0x0000000002F84540>
 >>> f.read(5)
 'nihao'
 >>> f.seek()

 Traceback (most recent call last):
   File "<pyshell#14>", line 1, in <module>
     f.seek()
 TypeError: seek() takes at least 1 argument (0 given)
 >>> f.tell()
 5L
 >>> lines=list(f)
 >>> for eachLine in lines:
     print eachLine

 wozhidao

 牟柏旭

 >>> f
 <open file 'E:\\tmp.txt', mode 'r' at 0x0000000002F84540>
 >>> f.read()
 ''
 >>> f.seek(0,0)
 >>> f.readline()
 'nihao\n'
 >>> f.seek(0,0)
 >>> fw=open('E:\\tmp.txt','w')
 >>> fw.write('let's go')

 SyntaxError: invalid syntax
 >>> fr=open('E:\\tmp1.txt','w')
 >>> fr.write('nihao')
 >>> fr.close()