code: def refresh_collections(self, accept=MEDIA_TYPE_TAXII_V20):
          
          url = self.url + "collections/"
          response = self._conn.get(url, headers={"Accept": accept})
  
          self._collections = []
          for item in response.get("collections", []):  # optional
              collection_url = url + item["id"] + "/"
              collection = Collection(collection_url, conn=self._conn,
                                      collection_info=item)
              self._collections.append(collection)
  
          self._loaded_collections = True
docs: Update the list of Collections contained by this API Root.
  
          This invokes the ``Get Collections`` endpoint.