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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 logsumexp(arr, axis=0):
 """Computes the sum of arr assuming arr is in the log domain. Returns log(sum(exp(arr))) while minimizing the possibility of over/underflow. Examples -------- 9.4586297444267107 9.4586297444267107 """

    arr = np.rollaxis(arr, axis)
    # Use the max to normalize, as with the log this is what accumulates
    # the less errors
    vmax = arr.max(axis=0)
    out = np.log(np.sum(np.exp(arr - vmax), axis=0))
    out += vmax
    return out