如何从每个列表项中获取字符串的特定部分？

import re

def get_specific_part_from_list(items, pattern):
    result = []
    for item in items:
        match = re.search(pattern, item)
        if match:
            result.append(match.group())
    return result

# 示例列表
items = ['abc123', 'def456', 'ghi789']

# 获取每个字符串的前两个字符
pattern = r'^.{2}'
result = get_specific_part_from_list(items, pattern)
print(result)  # 输出: ['ab', 'de', 'gh']

# 获取每个字符串的最后两个字符
pattern = r'.{2}$'
result = get_specific_part_from_list(items, pattern)
print(result)  # 输出: ['23', '56', '89']

# 获取每个字符串中的数字部分
pattern = r'\d+'
result = get_specific_part_from_list(items, pattern)
print(result)  # 输出: ['123', '456', '789']