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pickle and __slots__


I am trying to pickle an object, and I get:

TypeError: a class that defines __slots__ without defining
__getstate__ cannot be pickled

I didn't find __slots__ in the object or the class. Is there a way to
find it, or to to know which object or class causes the problem?


Oct 4 '07 #1
3 4580
JL wrote:

I am trying to pickle an object, and I get:

TypeError: a class that defines __slots__ without defining
__getstate__ cannot be pickled

I didn't find __slots__ in the object or the class. Is there a way to
find it, or to to know which object or class causes the problem?

Is this a subclass? Look at the parent classes.

John Nagle
Oct 4 '07 #2
Is this a subclass? Look at the parent classes.

Its class is a subclass of a similar class, but it indirectly
references instances of subclasses of asyncore.dispat cher or
asynchat.async_ chat. I don't think there are other particular classes.
If I remove the first references, pickle works. Anyway it seems that I
will have to mask the asyncore.dispat cher and asynchat.async_ chat
subclass instances which will not be relevant at unpickle time.

Oct 4 '07 #3
I added the following method to the 2 subclasses of
asyncore.dispat cher and asynchat.async_ chat and now pickle works:

def __getstate__(se lf):

Later I will probably modify this method so it returns something more
Thanks for your help! I was confused because I am not sure what can be
pickled or not.

Oct 4 '07 #4

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