'Check all inline model admin classes.'

def _check_inlines(self, obj):

    if (not isinstance(obj.inlines, (list, tuple))):
        return must_be('a    list    or    tuple', option='inlines', obj=obj, id='admin.E103')
    else:
        return list(chain.from_iterable((self._check_inlines_item(obj, obj.model, item, ('inlines[%d]' % index)) for (index, item) in enumerate(obj.inlines))))
