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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 leaveoneout(self):
 """Train & Test using leave one out"""

        traintestfile = self.fileprefix + '.train'
        options = "-F " + self.format + " " +  self.timbloptions + " -t leave_one_out"
        if sys.version < '3':
            self.api = timblapi.TimblAPI(b(options), b"")
        else:
            self.api = timblapi.TimblAPI(options, "")
        if self.debug:
            print("Enabling debug for timblapi",file=stderr)
            self.api.enableDebug()
        print("Calling Timbl API : " + options,file=stderr)
        if sys.version < '3':
            self.api.learn(b(traintestfile))
            self.api.test(b(traintestfile), b(self.fileprefix + '.out'),b'')
        else:
            self.api.learn(u(traintestfile))
            self.api.test(u(traintestfile), u(self.fileprefix + '.out'),'')
        return self.api.getAccuracy()