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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 cmu_mocap_49_balance(data_set='cmu_mocap'):
 """Load CMU subject 49's one legged balancing motion that was used by Alvarez, Luengo and Lawrence at AISTATS 2009."""

    train_motions = ['18', '19']
    test_motions = ['20']
    data = cmu_mocap('49', train_motions, test_motions, sample_every=4, data_set=data_set)
    data['info'] = "One legged balancing motions from CMU data base subject 49. As used in Alvarez, Luengo and Lawrence at AISTATS 2009. It consists of " + data['info']
    return data