from django.conf import settings
import random

class DebugForm(forms.ModelForm):
    
    def __init__(self, *args, **kwargs):
        super(DebugForm, self).__init__(*args, **kwargs)
        if kwargs.get('instance'):
            return
        if settings.DEBUG:
            for field in self.DEBUG_DATA.keys():
                val = random.choice(self.DEBUG_DATA[field])
                self.fields[field].initial = val

class MyForm(DebugForm):
    
    DEBUG_DATA = {
        'comment':['this is some sample data', 'this is some more sample data']
    }
    
    class Meta:
        
        model = YourModel