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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 read(self):
 """Reads the robots.txt URL and feeds it to the parser."""

        try:
            f = urllib.request.urlopen(self.url)
        except urllib.error.HTTPError as err:
            if err.code in (401, 403):
                self.disallow_all = True
            elif err.code >= 400:
                self.allow_all = True
        else:
            raw = f.read()
            self.parse(raw.decode("utf-8").splitlines())