code: def set_cookie(self, cookie):
          
          c = self._cookies
          self._cookies_lock.acquire()
          try:
              if cookie.domain not in c: c[cookie.domain] = {}
              c2 = c[cookie.domain]
              if cookie.path not in c2: c2[cookie.path] = {}
              c3 = c2[cookie.path]
              c3[cookie.name] = cookie
          finally:
              self._cookies_lock.release()
docs: Set a cookie, without checking whether or not it should be set.