new_contents: # -*- coding: utf-8 -*-
  
  from dlstats import constants
  from dlstats.utils import Downloader, clean_datetime
  from dlstats.fetchers._commons import Fetcher, Datasets, Providers, SeriesIterator
  from dlstats import errors
  
  VERSION = 1
  
  class DUMMY(Fetcher):
      
      def __init__(self, **kwargs):
          super().__init__(provider_name='DUMMY', version=VERSION, **kwargs)
          
          self.provider = Providers(name=self.provider_name,
                                    long_name='Dummy Fetcher',
                                    version=VERSION,
                                    region='World',
                                    website='http://www.example.org', 
                                    fetcher=self)
          
      def upsert_dataset(self, dataset_code):
          
          dataset = Datasets(provider_name=self.provider_name, 
                             dataset_code=dataset_code, 
                             name="My Dataset Name",
                             last_update=clean_datetime(), 
                             fetcher=self)
          
          fetcher_data = DUMMY_Data(dataset)
          dataset.series.data_iterator = fetcher_data
  
          return dataset.update_database()
              
      def build_data_tree(self):
          
          categories = []
  
          categories.append({
              "category_code": "c1",
              "name": "category 1",
              "doc_href": "http://www.example.org/c1",
              "datasets": [{
                  "name": "My Dataset Name", 
                  "dataset_code": "ds1",
                  "last_update": None, 
                  "metadata": None
              }]
          })
          
          return categories
      
  DUMMY_SAMPLE_SERIES = [
      {
          'provider_name': "DUMMY", 
          'dataset_code': "ds1",
          'name': "name1", 
          'key': "key1", 
          "slug": "dummy-ds1-key1",             
          'attributes': None,
          'dimensions': {"COUNTRY": "FRA"},
          'start_date': 10, 
          'end_date': 20,
          'frequency': "A",
          'values': [
              {
               "period": "2000", 
               "value": "1", 
               "ordinal": 10, 
               "attributes": {"OBS_STATUS": "A"}
              },
              {
               "period": "2001", 
               "value": "10", 
               "ordinal": 20, 
               "attributes": None
              },
          ],                
      }
  ] 
  
  class DUMMY_Data(SeriesIterator):
      
      def __init__(self, dataset):
          super().__init__(dataset)
  
          self.rows = self._process()
          
      def _process(self):
          for series in DUMMY_SAMPLE_SERIES:
              yield series, None
          
      def build_series(self, bson):
          bson["last_update"] = self.dataset.last_update
          return bson
          
      
subject: add Dummy Fetcher