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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 string_sanitize(string, tab_width=8):
 r""" strips, and replaces non-printable characters :param tab_width: number of spaces to replace tabs with. Read from `globals.tabwidth` setting if `None` :type tab_width: int or `None` ' foobar ' 'foo bar' 'foo bar' """


    string = string.replace('\r', '')

    lines = list()
    for line in string.split('\n'):
        tab_count = line.count('\t')

        if tab_count > 0:
            line_length = 0
            new_line = list()
            for i, chunk in enumerate(line.split('\t')):
                line_length += len(chunk)
                new_line.append(chunk)

                if i < tab_count:
                    next_tab_stop_in = tab_width - (line_length % tab_width)
                    new_line.append(' ' * next_tab_stop_in)
                    line_length += next_tab_stop_in
            lines.append(''.join(new_line))
        else:
            lines.append(line)

    return '\n'.join(lines)