import re
text = """SECTION 1. CHAPTER 1. Chapter title. Art. 1.- Lorem ipsum, blah, blah. Art 2.- More meaningless text. Art 3.- A little more text. CHAPTER 2. Another chapter. Art 4.- Lorem ipsum blah, blah, blah. Art. 5.- It's getting boring. SECTION 2. CHAPTER 1. Another chapter in another section. Art. 6.- The last text. SECTION 3. CHAPTER 1. Another chapter in another section. Art. 6.- The last text. SECTION 4. CHAPTER 1. Another chapter in another section. Art. 6.- The last text."""
print(dict(re.findall(r"(SECTION\s+\d+)\.\s*([^S]*(?:S(?!ECTION\s+\d+\.)[^S]*)*)", text)))
 

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