def url_for(endpoint, default="<STR_LIT>", **values):
try:<EOL><INDENT>return router.url_for(endpoint, force_external=True, values=values)<EOL><DEDENT>except Exception:<EOL><INDENT>logger.debug("<STR_LIT>"<EOL>"<STR_LIT>" % endpoint)<EOL>return router.url_for(default, force_external=True, values=values)<EOL><DEDENT>
Looks up the API URL for the given endpoint

    :param endpoint: The name of the registered route (aka endpoint)
    :type endpoint: string
    :returns: External URL for this endpoint
    :rtype: string/None