  from django.forms.models import (modelform_factory, modelformset_factory,
      inlineformset_factory, BaseInlineFormSet, modelform_defines_fields)
  from django.http import Http404, HttpResponseRedirect
  from django.http.response import HttpResponseBase
  from django.shortcuts import get_object_or_404
  from django.template.response import SimpleTemplateResponse, TemplateResponse
  from django.utils import six
  from django.utils.decorators import method_decorator
 
</s> remove         return db_field.formfield(**kwargs)
 </s> add         form_field = db_field.formfield(**kwargs)
        if isinstance(form_field.widget, SelectMultiple) and not isinstance(form_field.widget, CheckboxSelectMultiple):
            msg = _('Hold down "Control", or "Command" on a Mac, to select more than one.')
            help_text = form_field.help_text
            form_field.help_text = string_concat(help_text, ' ', msg) if help_text else msg
        return form_field
from django.forms.widgets import SelectMultiple, CheckboxSelectMultiple
  from django.forms.models import (modelform_factory, modelformset_factory,
      inlineformset_factory, BaseInlineFormSet, modelform_defines_fields)
from django.forms.widgets import SelectMultiple, CheckboxSelectMultiple
  from django.http import Http404, HttpResponseRedirect
  from django.http.response import HttpResponseBase
  from django.shortcuts import get_object_or_404
  from django.template.response import SimpleTemplateResponse, TemplateResponse
  from django.utils import six
  from django.utils.decorators import method_decorator
keep add keep keep keep keep keep keep
 Made m2m fields form help_text munging specific to admin widgets.

Refs #9321 and follow-up to e80de93af6a0a21a9063a55c4d6d20e3927243e9. 
django/contrib/admin/options.py