Object does not support item assignment error

python django loops dictionary
neurix picture neurix · Dec 17, 2011 · Viewed 107.6k times · Source

In my views.py I assign values before saving the form. I used to do it the following way:

projectForm.lat = session_results['lat']
projectForm.lng = session_results['lng']

Now, since the list of variables got a bit long, I wanted to loop over session_results with the following loop (as described by Adam here):

for k,v in session_results.iteritems():
    projectForm[k] = v

But I get the error 'Project' object does not support item assignment for the loop solution. I have trouble to understand why. Project is the model class, which I use for the ModelForm.

Thank you for your help!

Answer

Yuji 'Tomita' Tomita picture Yuji 'Tomita' Tomita · Dec 17, 2011

The error seems clear: model objects do not support item assignment. MyModel.objects.latest('id')['foo'] = 'bar' will throw this same error.

It's a little confusing that your model instance is called projectForm...

To reproduce your first block of code in a loop, you need to use setattr

for k,v in session_results.iteritems():
    setattr(projectForm, k, v)

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