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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 redirect(req, _log=pymagic.get_lazy_logger("redirect")):
 """ Redirect controller to emit a HTTP 301. """

    log = req.environ.get("wsgilog.logger", _log)
    target = req.relative_url(req.urlvars.to)
    log.info("Redirecting '%s' to '%s'" % (req.url, target))
    return exc.HTTPMovedPermanently(location=target)