text: from django import forms
  
  from .models import Reminder
  
  
  class ReminderInlineAdminForm(forms.ModelForm):
      class Meta:
          model = Reminder
          fields = ('user', 'interval', 'object_id', 'content_type',)
  
      def clean_user(self):
          user = self.cleaned_data['user']
          if not user.email:
              raise forms.ValidationError(
                  "User doesn't have an email address, please pick a different user or add an "
                  "email address"
              )
          return user
  
      def validate_unique(self):
          """
          Add this method because django doesn't validate correctly because required fields are
          excluded.
          """
          unique_checks, date_checks = self.instance._get_unique_checks(exclude=[])
          errors = self.instance._perform_unique_checks(unique_checks)
          if errors:
              self.add_error(None, errors)
  