 Python can serve as a scripting language for web applications , e.g. , via mod _ <unk> for the Apache web server . With Web Server Gateway Interface , a standard API has evolved to facilitate these applications . Web frameworks like Django , Pylons , Pyramid , <unk> , <unk> , Tornado , Flask , Bottle and <unk> support developers in the design and maintenance of complex applications . Pyjamas and <unk> can be used to develop the client @-@ side of Ajax @-@ based applications . <unk> can be used as data mapper to a relational database . Twisted is a framework to program communications between computers , and is used ( for example ) by Dropbox . 
