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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 _parse_array_bitmap(self, block):
 """ Parse the bitmap status of the md array. { 'total_pages': '1', 'allocated_pages': '1', 'page_size': 4096, 'chunk_size': 67108864 } :return: dictionary of bitmap status information :rtype: dict """

        array_bitmap_regexp = re.compile(
            '^ *bitmap: (?P<allocated_pages>[0-9]*)/'
            '(?P<total_pages>[0-9]*) pages '
            '\[(?P<page_size>[0-9]*)KB\], '
            '(?P<chunk_size>[0-9]*)KB chunk.*$',
            re.MULTILINE
        )

        regexp_res = array_bitmap_regexp.search(block)

        # bitmap is optionally in mdstat
        if not regexp_res:
            return None

        array_bitmap_dict = regexp_res.groupdict()
        array_bitmap_dict_sanitizied = {}

        # convert all values to int
        for key, value in array_bitmap_dict.iteritems():
                if not value:
                    continue
                array_bitmap_dict_sanitizied[key] = int(value)

        # convert page_size to bytes
        array_bitmap_dict_sanitizied['page_size'] *= 1024

        # convert chunk_size to bytes
        array_bitmap_dict_sanitizied['chunk_size'] *= 1024

        return array_bitmap_dict