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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 zcr(data):
 """Computes zero crossing rate of segment"""

    data = np.mean(data, axis=1)

    count = len(data)
    countZ = np.sum(np.abs(np.diff(np.sign(data)))) / 2
    return (np.float64(countZ) / np.float64(count - 1.0))