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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 make_request(self, url, params, auth=None):
 """ Prepares a request from a url, params, and optionally authentication. """

        req = urllib2.Request(url + urllib.urlencode(params))

        if auth:
            req.add_header('AUTHORIZATION', 'Basic ' + auth)

        return urllib2.urlopen(req)