docs: def get_associations(self, env):
          """
          Get all the associations for this env.
  
          Root cannot have associations, so return None for root.
  
          returns a map of hostnames to environments.
          """
  
          if env.is_root:
              return None
  
          associations = self.associations.get_all()
          return [assoc for assoc in associations
                  if associations[assoc] == self._get_view_path(env)]