我想从一篇文章中提取章节和小节以及相应的内容。我有下面的代码使用正则表达式，但代码不能检测到的小节。如何解决？

import re

def extract_sections_and_content(text):
    pattern = r'(?P<section>^\d+(?:\.\d+)*(?:\s+\S+)?\s+[A-Za-z]+)\n(?P<content>(?:(?!\d+(?:\.\d+)*(?:\s+\S+)?\s+[A-Za-z]+|\n\d+(?:\.\d+)*(?:\s+\S+)?\s+[A-Za-z]+).)*)'
    matches = re.finditer(pattern, text, re.DOTALL | re.MULTILINE)
    section_content_pairs = [(re.sub(r'^\d+(?:\.\d+)*(?:\s+\S+)?\s+', '', match.group('section').strip()), match.group('content').strip()) for match in matches]
    return dict(section_content_pairs)

# Example usage:
text = """
1 Introduction
Lorem ipsum dolor sit amet, consectetur adipiscing elit.
2 Background
Praesent euismod, arcu quis fermentum pulvinar, urna ex euismod ex.
2.1.2 Introduction to Topic
Vestibulum nec lorem eu ligula faucibus cursus.
3 Conclusion
Sed sed malesuada magna, at dignissim quam.
"""

result = extract_sections_and_content(text)
print(result)

字符串
我得到的结果：

{'Introduction': 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.', 
 'Background': 'Praesent euismod, arcu quis fermentum pulvinar, urna ex euismod ex.', 
 'Conclusion': 'Sed sed malesuada magna, at dignissim quam.'}

型
我想要的结果是：

{'Introduction': 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
 'Background': 'Praesent euismod, arcu quis fermentum pulvinar, urna ex euismod ex.',
 'Introduction to Topic': 'Vestibulum nec lorem eu ligula faucibus cursus.',
 'Conclusion': 'Sed sed malesuada magna, at dignissim quam.'}

型