请教一个关于cPickle的小问题

[STUDENTzyr]

>>> f = file(filename,'a')
>>> for i in range(10):
	a = i * 2
	cPickle.dump(a,f)

	
>>> f.close()
>>> f = file(filename,'r')
>>> re = cPickle.load(f)
>>> re
0
>>> f = file(filename,'a')
>>> for i in range(10):
	cPickle.dump(i,f)

	
>>> ff = file(filename,'r')
>>> a = cPickle.load(ff)
>>> a
0

为什么结果都是0呢，我想存入一串对象，该怎么办好

[iambic]

cPickle.dump(range(10), f)

[izee]

#!/usr/bin/python
import cPickle

filename = "test"
f = file(filename,"a")
for i in range(10):
    a=i*2
    cPickle.dump(a,f)

f.close()

f = file(filename,'r')
try:
    while True:
        re = cPickle.load(f)
        print re
except EOFError:
    print '\n $f Load Completed ....'
f.close()

f = file(filename,'a')
for i in range(10):
    cPickle.dump(i,f)
f.close()

ff = file(filename,'r')
try:
   while True:
       a = cPickle.load(ff)
       print a
except EOFError:
    print '\n $ff Load completed ....'