from pathlib import Path
from zipfile import ZipFile
p=Path('/tmp/lead-32693-r2/capture-1/project/slides.odp')
with ZipFile(p) as z: entries={n:z.read(n) for n in z.namelist()}
s=entries['content.xml'].decode()
for i in range(1,4):
 s=s.replace(f'<text:p>Synthetic ODP slide {i}</text:p>',f'<text:p>Synthetic ODP slide {i}</text:p>'+''.join(f'<text:p>Slide {i}, paragraph {n}. Synthetic reading position retained.</text:p>' for n in range(50)))
entries['content.xml']=s.encode()
with ZipFile(p,'w') as z:
 for n,b in entries.items():z.writestr(n,b)