[Tutor] how to shelve classes

[Payal]

Hi,
I want to carry my classes around, so I wrote foo.py as,

#!/usr/bin/python

import pickle, shelve

f = shelve.open('movies')

class F(object) :
    def __init__(self, amt) : self.amt = amt
    def dis(self) : print 'Amount : ', self.amt
    def add(self, na) :
        self.amt += na
        F.dis(self)

f['k'] = F
x=F(99)
f['k2']=x

Now in python interpreter I get,
>>> import shelve
>>> f = shelve.open('movies')
>>> F2=f['k']
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.6/shelve.py", line 122, in __getitem__
    value = Unpickler(f).load()
AttributeError: 'module' object has no attribute 'F'

How do I carry around my classes and instances?

With warm regards,
-Payal
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