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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_url(self, session, uri):
 """ Helper method to get the full url """

        url = session.url
        if uri:
            slash = '' if uri.startswith('/') else '/'
            url = "%s%s%s" % (session.url, slash, uri)
        return url