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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 _get_base_url(request):
 """ Construct a base URL, given a request object. This comprises the protocol prefix (http:// or https://) and the host, which can include the port number. For example: http://www.openquake.org or https://www.openquake.org:8000. """

    if request.is_secure():
        base_url = 'https://%s'
    else:
        base_url = 'http://%s'
    base_url %= request.META['HTTP_HOST']
    return base_url