code: def setup():
      
      # create an index template
      index_template = BlogPost._index.as_template(ALIAS, PATTERN)
      # upload the template into elasticsearch
      # potentially overriding the one already there
      index_template.save()
  
      # create the first index if it doesn't exist
      if not BlogPost._index.exists():
          migrate(move_data=False)
docs: Create the index template in elasticsearch specifying the mappings and any
      settings to be used. This can be run at any time, ideally at every new code
      deploy.