+ metadata = metadata_from_text(text)
+ for category in Category.objects.all():
+ values = metadata.get(category.dc_tag)
+ if not category.multiple:
+ values = [values]
+ if not values:
+ values = []
+ for value in values:
+ if not category.tag_set.filter(dc_value=value):
+ raise ValidationError('Invalid value for dc:%s: %s' % (category.dc_tag, value))