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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def oq_server_context_processor(request):
 """ A custom context processor which allows injection of additional context variables. """


    context = {}

    context['oq_engine_server_url'] = ('//' +
                                       request.META.get('HTTP_HOST',
                                                        'localhost:8800'))
    # this context var is also evaluated by the STANDALONE_APPS to identify
    # the running environment. Keep it as it is
    context['oq_engine_version'] = oqversion
    context['server_name'] = settings.SERVER_NAME
    return context