Check the security hash.

def clean_security_hash(self):
        """Check the security hash."""
        security_hash_dict = {
            'content_type': self.data.get("content_type", ""),
            'object_pk': self.data.get("object_pk", ""),
            'timestamp': self.data.get("timestamp", ""),
        }
        expected_hash = self.generate_security_hash(**security_hash_dict)
        actual_hash = self.cleaned_data["security_hash"]
        if not constant_time_compare(expected_hash, actual_hash):
            raise forms.ValidationError("Security hash check failed.")
        return actual_hash