以下shell脚本是什么意思，转换成python是什么样的。ComNvmeDevNameInfoGet() { local slot_info="$1" local ret_file="$2" local ctrl_str="$3" local slot_id="" local slot_temp="" local slot_id_get="" local contrl_num="" local test_scene="" local ctrl_id=0 ls /dev/ | grep "nvme[0-9]\{1,\}" | grep -v "nvme[0-9]\{1,\}n" >nvme_info.txt slot_id=$(echo "${slot_info}" | sed 's/^0*//g') slot_id=$[slot_id+0] slot_id=$[slot_id-1] set +x while read contrl_num || [[ ! -z ${contrl_num} ]] do if [ "0" == "${ctrl_id}" ];then find /sys/devices -name "${contrl_num}" > ${contrl_num}_bus_info.txt else rm -f ${contrl_num}_bus_info.txt dos2unix ${contrl_num}_bus_info.txt fi #兼容服务器的PCIE链路 if grep -iw "FT2-MP1" /root/TestPlat/common/test_scene.ini ;then slot_temp=$(cat ${contrl_num}_bus_info.txt | awk -F / '{print $5}' | awk -F "." '{print $2}') else slot_temp=$(cat ${contrl_num}_bus_info.txt | awk -F "/" '{print $7}' | cut -b 9-10) fi slot_id_get=$[0x${slot_temp}+0] if [ "${slot_id_get}" = "${slot_id}" ];then set -x echo "${slot_id}:/dev/${contrl_num}:Ctrl${ctrl_id}" echo "/dev/${contrl_num}" >"${ret_file}" return 0 fi done < nvme_info.txt set -x echo "$(date +"%y-%m-%d %H:%M:%S") can not get nvme controller ctrl${ctrl_id} info,slot${slot_info}." | tee -a error.txt return 1

这个shell脚本的作用是根据输入的slot_info（slot id）来获取对应的NVMe控制器的设备名，并将其输出到指定的文件中。具体流程如下：

1. 将所有/dev/目录下的名字类似于“nvme[0-9]”但不包含“nvme[0-9]n”的文件名存储在nvme_info.txt文件中。

2. 将输入的slot_info转换为十进制，并减去1，得到slot_id。

3. 遍历nvme_info.txt中的每个文件名，获取其对应的控制器编号contrl_num。

4. 根据contrl_num在/sys/devices目录下查找对应的总线信息文件，并将其存储在contrl_num_bus_info.txt文件中。

5. 根据服务器型号的不同，从contrl_num_bus_info.txt中提取出对应的PCIe插槽编号slot_temp。

6. 将slot_temp转换为十进制，得到slot_id_get。

7. 如果slot_id_get与slot_id相等，则将控制器设备名输出到ret_file文件中，并返回0表示成功。

8. 如果遍历完所有的文件名仍然没有找到对应的控制器设备名，则将错误信息输出到error.txt文件中，并返回1表示失败。

将其转换成Python代码大致如下：

import os
import re
import datetime

def ComNvmeDevNameInfoGet(slot_info, ret_file, ctrl_str):
    with open("nvme_info.txt", "w") as f:
        for file in os.listdir("/dev/"):
            if re.match("nvme[0-9]+", file) and not re.match("nvme[0-9]+n", file):
                f.write(file + "\n")

    slot_id = int(slot_info.lstrip("0"))
    slot_id -= 1

    ctrl_id = 0
    with open("nvme_info.txt", "r") as f:
        for contrl_num in f:
            contrl_num = contrl_num.strip()
            if ctrl_id == 0:
                with open(f"/sys/devices/*/pci*/{contrl_num}/", "w") as bus_info_file:
                    bus_info_file.write(contrl_num)
            else:
                os.remove(f"{contrl_num}_bus_info.txt")
                os.system(f"dos2unix {contrl_num}_bus_info.txt")

            if "FT2-MP1" in open("/root/TestPlat/common/test_scene.ini").read():
                with open(f"{contrl_num}_bus_info.txt", "r") as bus_info_file:
                    slot_temp = re.search(r"/pci([0-9a-fA-F]{2}).*/", bus_info_file.read()).group(1)
            else:
                with open(f"{contrl_num}_bus_info.txt", "r") as bus_info_file:
                    slot_temp = re.search(r"/pci.*/(.*):.*", bus_info_file.read()).group(1)[8:10]

            slot_id_get = int(slot_temp, 16)
            if slot_id_get == slot_id:
                with open(ret_file, "w") as ret_file:
                    ret_file.write(f"/dev/{contrl_num}")
                return f"{slot_id}:/dev/{contrl_num}:Ctrl{ctrl_id}"
            ctrl_id += 1

    with open("error.txt", "a") as error_file:
        error_file.write(f"{datetime.datetime.now().strftime('%y-%m-%d %H:%M:%S')} can not get nvme controller ctrl{ctrl_id} info,slot{slot_info}.\n")
    return 1