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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 nextpow2(value):
 """Compute the nearest power of two greater or equal to the input value"""

    if value >= 1:
        return 2**np.ceil(np.log2(value)).astype(int)
    elif value > 0:
        return 1
    elif value == 0:
        return 0
    else:
        raise ValueError('Value must be positive')