/Python/Django pre_save get old instance

Django pre_save get old instance

@receiver(pre_save, sender=A)
def signal_product_manage_latest_version_id(sender, instance, update_fields=None, **kwargs):
    try:
        old_instance = A.objects.get(id=instance.id)
    except A.DoesNotExist:  # to handle initial object creation
        return None  # just exiting from signal
    # your code to with 'old_instance'

Source: stackoverflow.com

Similar codes

0 vote288 views1 answer
Date format django template filter
Python Django
18 votes254 views5 answers
Plot histogram python
Python
4 votes270 views3 answers
Pandas dataframe drop rows with -ve in column value
Python
0 vote237 views1 answer
Iniciar servidor en Django
Python
1 vote271 views2 answers
Valueerror: failed to convert a numpy array to a tensor (unsupported object type int).
Python
0 vote304 views1 answer
Np.eye(5)[list]
Python
0 vote302 views1 answer
How do you say not equal to python
Python
0 vote283 views4 answers
Beautifulsoup parent
Python
2 votes249 views1 answer
Python method to check for uppercase character
Python
1 vote256 views1 answer
Pygame get if button is released
Python