code: def contains_raw(self, etag):
          
          etag, weak = unquote_etag(etag)
          if weak:
              return self.contains_weak(etag)
          return self.contains(etag)
docs: When passed a quoted tag it will check if this tag is part of the
          set.  If the tag is weak it is checked against weak and strong tags,
          otherwise strong only.