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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(use_ssl, instance=None, host=None):
 """Formats the base URL either `host` or `instance` :return: Base URL string """


        if instance is not None:
            host = ("%s.service-now.com" % instance).rstrip('/')

        if use_ssl is True:
            return "https://%s" % host

        return "http://%s" % host