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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 _replace(self, url):
 """ Change URLs with absolute paths so they are rooted at the correct location. """

        segments = url.split('/')
        if segments[0] == '':
            root = self.rootURL(self.request)
            if segments[1] == 'Mantissa':
                root = root.child('static').child('mantissa-base')
                segments = segments[2:]
            elif segments[1] in self.installedOfferingNames:
                root = root.child('static').child(segments[1])
                segments = segments[2:]
            for seg in segments:
                root = root.child(seg)
            return str(root)
        return url