Регулярные выражения

import re
bands = list ()
filename = 'TEXT.txt'
for line in open (filename).readlines():
    if not line.startswith(" P") and not line.startswith("-"):
        bands.append(line.strip())
 
print(bands)
filename = 'bands_sorted.txt'
with open (filename, 'w') as fout:
    for band in bands:
            fout.write (band + '\n')

import re
 
text = '!4212345SFRUB FIO 02/05/1961 M'
 
finds = re.findall('!(\d{7})([A-Z]{2})([A-Z]{3}) ([A-Z]{3}) (\d{2}/\d{2}/\d{4}) ([A-Z])', text, re.IGNORECASE)
template = '{0}{1} {2} {3} {4} {5}'
for f in finds:
    print(template.format(*f))

text = '!4212345SFRUB FIO 02/05/1961 M'
print(re.sub(r'(?=RUB)', ' ', text[1:]))
# 4212345SF RUB FIO 02/05/1961 M

import re
 
with open('in.txt', 'r') as f_in, open('out.txt', 'w') as f_out:
    lines = f_in.readlines()
    f_out.write(''.join(lines[:3]))
    result = [re.sub(r'(?<=\d{8})(?=[A-Z]{3} )', ' ', line[1:]) for line in lines if line.startswith('!')]
    f_out.write(''.join(result))
    f_out.write(f'\n*{len(result)} POZICII\nEND FILE')

r'(?<=\w{9})(?=[A-Z]{3} )'
# или вообще конкретизируй валюту 
r'(?<=\w{9})(?=(RUB|EUR|USD) )'