code: def save_service(self, service, overwrite=True):
          
          name = namesgenerator.get_sane_name(service.name)
          if not name:
              name = namesgenerator.get_random_name()
              if self.collection.count_documents({'name': name}) > 0:
                  name = namesgenerator.get_random_name(retry=True)
          # check if service is already registered
          if self.collection.count_documents({'name': name}) > 0:
              if overwrite:
                  self.collection.delete_one({'name': name})
              else:
                  raise Exception("service name already registered.")
          self.collection.insert_one(Service(
              name=name,
              url=baseurl(service.url),
              type=service.type,
              purl=service.purl,
              public=service.public,
              auth=service.auth,
              verify=service.verify))
          return self.fetch_by_name(name=name)
docs: Stores an OWS service in mongodb.