How to split paragraphs by specific starts and ends with specific rules by python re or something?

It follows very similar logic to another question answered moments ago. https://docs.python.org/3/library/re.html

#! /usr/bin/env python3
import re

original = 'Original.txt'
new = 'Padded.txt'

Starts = (
    r'AA .+',
    r'BBBB BB.+BBB.+B',
    r'CCCC .+ CCC',
)

Ends = (
    r'EE .+ EEE',
    r'FF.+FFF',
    r'.+ GGG'
)

with open( original, 'r' ) as f:
    output = open( new, 'a+' )
    start = False

    for line in f:
        end = False

        for pattern in Starts:
            start_chars = line[:25]
            if re .search( pattern, start_chars ) != None:
                start = True

        for pattern in Ends:
            end_chars = line[-15:]
            if re .search( pattern, end_chars ) != None:
                start = False
                end = True

        if end:  output .write( line +'\n' )
        elif start:  output .write( line )

1 zzz AA zzz AAA zzzz zzz zzz zzzz zzzz zzzz zzz
2 zzzzz AA zzz zzz AAA zzzz zzzzz zzzzz zzzzz zzzz
3 zzz zzzz zzz zzz zzzz zzzz zzz zzzz EE zzz EEE

6 BBBB BB zzzz BBB zz B zzzzzz zzzz zzzz zzzz zzzz zz
7 zzz zzz zzzz zzzz zzz zzzzz zzzz zzzzz zzzzz FF FFF zzz

8 CCCC zzz CCC zzzz zz zzzz zzzz zzz zzz GG G GGG

9 zzz AA zz AAA zzzz zzz zzz zzz FF zz FFF

10 AA zzzz AAA zzzz zzzz zzzz zzzzz zzzzz
11 zz CCCC zzz CCC zzzz zzzz zzzz zzzz zzzz zz
12 zzzz zzz zzzzz zzzzz zzzzz zzzzz zzzz zzzz EE zz EEE

13 zz AA zzz
14 AAA zzz zzz zzzz zzzz GG zz GGG

15 BBBB BB BBB zz B GG zz G
16 zzz GGG

thx @Doyousketch2. i edited your code then it works better.

try:
    file = open("Padded1.txt","r+")
    file.truncate(0)
    file.close()
except:
    pass

import re

original = 'Original1.txt'
new = 'Padded1.txt'

result = []

with open( original, 'r' ) as f:
    output = open( new, 'a+' )
    start = False

    for line in f:
        end = False

        for pattern in Starts:
            start_chars = line[:30]
            if re .search( pattern, start_chars ) != None:
                start = True

        for pattern in Ends:
            end_chars = line[-20:]
            if re .search( pattern, end_chars ) != None:
                #####start = False
                end = True

        if end and start:  
            output .write( line +'\n\n\n' )
            result.append(line +'\n\n\n')
            start = False
            end = False
            
        elif start:
            output .write( line )
            result.append(line)
            end = False
output.close()

if start == True and end == False:
    #remove last line from a text line in python
    fd=open("Padded1.txt","r")
    d=fd.read()
    fd.close()
    sep = "\n\n\n\n"
    s=sep.join(d.split(sep)[:-1])
    fd=open("Padded1.txt","w+")
    for i in range(len(s)):
        fd.write(s[i])
    fd.close()
    
elif start == False and end == True:
    #remove last line from a text line in python
    fd=open("Padded1.txt","r")
    d=fd.read()
    fd.close()
    sep = "\n\n\n\n"
    s=sep.join(d.split(sep)[:-1])
    fd=open("Padded1.txt","w+")
    for i in range(len(s)):
        fd.write(s[i])
    fd.close()



# Comparing Two Text Files, Removing the duplicate lines, and Writing results to a new text file

small_file = open('Original1.txt','r')
long_file = open('Padded1.txt','r')
output_file = open('output_file.txt','w')

try:
    small_lines = small_file.readlines()
    small_lines_cleaned = [line.rstrip().lower() for line in small_lines]
    long_file_lines = long_file.readlines()
    long_lines_cleaned = [line.rstrip().lower() for line in long_file_lines]

    for line in small_lines_cleaned:
        if line not in long_lines_cleaned:
            output_file.writelines(line + '\n')

finally:
    small_file.close()
    long_file.close()
    output_file.close()
    
print('Done')