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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(event, WORD=True):
 """ Kill the word behind point, using whitespace as a word boundary. Usually bound to ControlW. """

    buff = event.current_buffer
    pos = buff.document.find_start_of_previous_word(count=event.arg, WORD=WORD)

    if pos is None:
        # Nothing found? delete until the start of the document.  (The
        # input starts with whitespace and no words were found before the
        # cursor.)
        pos = - buff.cursor_position

    if pos:
        deleted = buff.delete_before_cursor(count=-pos)

        # If the previous key press was also Control-W, concatenate deleted
        # text.
        if event.is_repeat:
            deleted += event.cli.clipboard.get_data().text

        event.cli.clipboard.set_text(deleted)
    else:
        # Nothing to delete. Bell.
        event.cli.output.bell()