class BaseConstraint

def clone(self)

    def clone(self):
        _, args, kwargs = self.deconstruct()
        return self.__class__(*args, **kwargs)

def constraint_sql(self, model, schema_editor)

    def constraint_sql(self, model, schema_editor):
        raise NotImplementedError("This method must be implemented by a subclass.")

def contains_expressions(self)

def create_sql(self, model, schema_editor)

    def create_sql(self, model, schema_editor):
        raise NotImplementedError("This method must be implemented by a subclass.")

def deconstruct(self)

    def deconstruct(self):
        path = "%s.%s" % (self.__class__.__module__, self.__class__.__name__)
        path = path.replace("django.db.models.constraints", "django.db.models")
        kwargs = {"name": self.name}
        if (
            self.violation_error_message is not None
            and self.violation_error_message != self.default_violation_error_message
        ):
            kwargs["violation_error_message"] = self.violation_error_message
        if self.violation_error_code is not None:
            kwargs["violation_error_code"] = self.violation_error_code
        return (path, (), kwargs)

def get_violation_error_message(self)

    def get_violation_error_message(self):
        return self.violation_error_message % {"name": self.name}

def remove_sql(self, model, schema_editor)

    def remove_sql(self, model, schema_editor):
        raise NotImplementedError("This method must be implemented by a subclass.")

def validate(self, model, instance, exclude=None, using='default')

    def validate(self, model, instance, exclude=None, using=DEFAULT_DB_ALIAS):
        raise NotImplementedError("This method must be implemented by a subclass.")