python - Appending to CommaSeperatedIntegerfield in django -

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i created model has commaseparatedintegerfield

models.py

class forumposts(models.model):      ....     path = models.commaseparatedintegerfield(blank=true,max_length=50)     ...

i want use model , defined view below views.py

def create_forum_post(request, ..):      ...     forumpost.path.append(forumpost_id)     ...

i encountered situation had append forumpost_id integer path defined commaseperatedintegerfield. while debugging got error

'unicode' object has no attribute 'append'.

i think might due lack of comma tried lot of variations of same code unable add forumpost_id path. in advance

commaseparatedintegerfield's value not deserialized automatically, feature of field type validation (it must comma seperated integers).

you need retrieve field value, deserialize it, append new integer, serialize , save back.

edit 1:

example: 

class forumposts(models.model):     # ...      def append_to_path(self, value):         path_list = self.path.split(',')         path_list.append(value)         self.path = ','.join(path_list)

usage:

forumpost.append_to_path(forumpost_id) forumpost.save() # save validate if path correct

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