docs: def build_workspace_path(user_id, workflow_id=None):
      """Build user's workspace relative path.
  
      :param user_id: Owner of the workspace.
      :param workflow_id: Optional parameter, if provided gives the path to the
          workflow workspace instead of just the path to the user workspace.
      :return: String that represents the workspace relative path.
          i.e. users/0000/workflows/0034
      """
      workspace_path = os.path.join('users', str(user_id), 'workflows')
      if workflow_id:
          workspace_path = os.path.join(workspace_path, str(workflow_id))
  
      return workspace_path