Django is relatively slow but it is rare that the language is the slowest thing in the chain. It is is usually (by far) disk access, ie for medias, followed but database queries. Most of the load of YouTube comes from medias. Videos are hyper heavy.
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django-responsive a utility application for building responsive websites in Django . This tool is meant to complement the use of CSS media queries and help solve problems with fixed width elements such as advertisements or embedded video. Now you and conditionally render content based on the device size or type.
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Quickstart
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