def etag_matches?(list, new_resource = request.post?)
      return !new_resource if list == '*'
      list.to_s.split(/\s*,\s*/).include? response['ETag']
    end
def etag_matches?(list, new_resource = request.post?)
      return !new_resource if list == '*'
      list.to_s.split(/\s*,\s*/).include? response['ETag']
    end
Helper method checking if a ETag value list includes the current ETag.