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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 _unix_word_rubout(text, pos):
 """ Kill the word behind pos, using white space as a word boundary. """

    words = text[:pos].rsplit(None, 1)
    if len(words) < 2:
        return text[pos:], 0
    else:
        index = text.rfind(words[1], 0, pos)
        return text[:index] + text[pos:], index