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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 log_mask_zero(a):
 """Computes the log of input probabilities masking divide by zero in log. Notes ----- During the M-step of EM-algorithm, very small intermediate start or transition probabilities could be normalized to zero, causing a *RuntimeWarning: divide by zero encountered in log*. This function masks this unharmful warning. """

    a = np.asarray(a)
    with np.errstate(divide="ignore"):
        return np.log(a)