def wait_for_all(self, objects, timeout=<NUM_LIT>):
start = time.time()<EOL>while True:<EOL><INDENT>all_exist = True<EOL>for obj in objects:<EOL><INDENT>if not obj.exists():<EOL><INDENT>all_exist = False<EOL>break<EOL><DEDENT><DEDENT>if all_exist:<EOL><INDENT>return<EOL><DEDENT>if time.time() - start > timeout:<EOL><INDENT>raise PocoTargetTimeout('<STR_LIT>', objects)<EOL><DEDENT>self.sleep_for_polling_interval()<EOL><DEDENT>
Wait until all of given UI proxies show up before timeout.
All UI proxies will be polled periodically. See option :py:class:`poll_interval <poco.pocofw.Poco>` in 
``Poco``'s initialization for more details.

Args:
    objects (Iterable<:py:class:`UIObjectProxy <poco.proxy.UIObjectProxy>`>): iterable object of the given UI 
     proxies
    timeout (:obj:`float`): timeout in seconds, default is 120s

Raises:
    PocoTargetTimeout: when not all of UI proxies appeared before timeout