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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 openattachment(self, attachid):
 """ Get the contents of the attachment with the given attachment ID. Returns a file-like object. """

        attachments = self.get_attachments(None, attachid)
        data = attachments["attachments"][str(attachid)]
        xmlrpcbinary = data["data"]

        ret = BytesIO()
        ret.write(xmlrpcbinary.data)
        ret.name = data["file_name"]
        ret.seek(0)
        return ret