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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 rollout(self, **kwargs):
 """Generate x for open loop movements. """

        if kwargs.has_key('tau'):
            timesteps = int(self.timesteps / kwargs['tau'])
        else: 
            timesteps = self.timesteps
        self.x_track = np.zeros(timesteps)
        
        self.reset_state()
        for t in range(timesteps):
            self.x_track[t] = self.x 
            self.step(**kwargs)

        return self.x_track