new_contents: from ckan.lib.navl.validators import ignore_empty, ignore
  from ckan.logic.validators import (
      name_validator, boolean_validator, is_positive_integer, isodate)
  
  
  def default_inventory_entry_schema():
      schema = {
          'id': [ignore_empty, unicode],
          'title': [not_empty, unicode, name_validator],
          'group_id': [group_id_exists],
          'is_recurring': [boolean_validator],
          'recurring_interval': [is_positive_integer],
          'last_added_dataset_timestamp': [isodate],
      }
      return schema
  
subject: Add default_inventory_entry_schema #3