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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 human_readable_digit(number):
 """ Return a digit in a human-readable string form. :param number: The obfuscated number. :type number: float :returns: A more human-readable version of the input number. :rtype: str """


    if 0 >= number:
        return "{0:.1f} ".format(number)

    word = ["", "thousand", "million", "billion", "trillion"]
    millidx = max(0, min(len(word)-1, int(np.floor(np.log10(abs(number))/3.0))))
    return "{0:.1f} {1}".format(number/10**(3*millidx), word[millidx])