如何让Django验证器动态化？

from django.core.exceptions import ValidationError
from django.core.validators import Validator

class DynamicValidator(Validator):
    def __init__(self, condition):
        self.condition = condition

    def __call__(self, value):
        if not self.condition(value):
            raise ValidationError('Validation failed.')

from django.db import models

def is_even(value):
    return value % 2 == 0

class MyModel(models.Model):
    my_field = models.IntegerField(validators=[DynamicValidator(is_even)])

from django import forms

class MyForm(forms.Form):
    my_field = forms.IntegerField()

    def clean_my_field(self):
        value = self.cleaned_data['my_field']
        if value > 10:
            self.fields['my_field'].validators.append(DynamicValidator(is_even))
        return value