how to check if a post status was changed from live to cancel in django?

Using Django Forms & APIs
3

This is the model that is been worked on


class Predictions(models.Model):
    prediction_topic = models.ForeignKey(PredictionTopic, on_delete=models.SET_NULL, null=True, blank=True, related_name="prediction_topic")
    user = models.ForeignKey(User, on_delete=models.SET_NULL, null=True)
    status = models.CharField(choices=STATUS, max_length=100, default="in_review")
    participants = models.ManyToManyField(User, related_name="participants", blank=True)

This is the form


class PredictionForm(forms.ModelForm):
    image = ImageField(widget=FileInput)
    class Meta:
        model = Predictions
        fields = [
            'prediction_topic',
            'status',
        ]