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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 to_disk_indices(value):
 """Convert following input to disk indices Sample input: ``` Disks: Bus 0 Enclosure 0 Disk 9 Bus 1 Enclosure 0 Disk 12 Bus 1 Enclosure 0 Disk 9 Bus 0 Enclosure 0 Disk 4 Bus 0 Enclosure 0 Disk 7 ``` :param value: disk list :return: disk indices in list """

    ret = []
    p = re.compile(r'Bus\s+(\w+)\s+Enclosure\s+(\w+)\s+Disk\s+(\w+)')
    if value is not None:
        for line in value.split('\n'):
            line = line.strip()
            if len(line) == 0:
                continue
            matched = re.search(p, line)
            if matched is None or len(matched.groups()) < 3:
                continue
            else:
                ret.append('{}_{}_{}'.format(*matched.groups()))
    return ret