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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 get_size_str(size):
 """ Formats a byte size as a string. The returned string is no more than 9 characters long. """

    if size == 0:
        magnitude = 0
        level = 0
    else:
        magnitude = math.floor(math.log(size, 10))
        level = int(min(math.floor(magnitude // 3), 4))
    return ('%d' if level == 0 else '%.2f') % (float(size) / 2**(level*10)) + ' ' + SIZE_LEVEL[level]