Django Model instance value in ModelForm constructor -

i create dynamic form based on modelform. aim add fields information in json field.

class myform(forms.modelform):     class meta:         model = mymodel         fields = ['name', 'json']       def __init__(self, *args, **kwargs):         super(myform, self).__init__(*args, **kwargs)          [ create fields here] 

i can create fields dynamically this:

    variables = ('var_1', 'var_2',)      v in variables:         self.fields[v] = forms.charfield(label=v) 

now, replace variables json.variables value. tried this: self.fields['json'].initial, self.fields['json'].data, self.fields['json'].cleaned_data without success.

do know how can have access model value?

finally solution quite easy. have use self.instance.json.