parameters: (sheet_id, user_id)
docstring: Deletes the activity feed item for a sheet publication
      (for when a user unpublishes a sheet)
docstring_summary: Deletes the activity feed item for a sheet publication
      (for when a user unpublishes a sheet)
docstring_tokens: Deletes the activity feed item for a sheet publication ( for when a user unpublishes a sheet )
function: def delete_sheet_publication(sheet_id, user_id):
      """
      Deletes the activity feed item for a sheet publication
      (for when a user unpublishes a sheet)
      """
      db.history.remove({
              "user": user_id,
              "sheet": sheet_id,
              "rev_type": "publish sheet"
          })
function_tokens: def delete_sheet_publication ( sheet_id , user_id ) : db . history . remove ( { "user" : user_id , "sheet" : sheet_id , "rev_type" : "publish sheet" } )