import re
bases = ['"../matlab/license_admin.pdf" abc "vfv"', '"license_admin.pdf" xyz']
for base in bases:
m = re.search(r'"(.*?\.pdf)', base)
if m:
print(m.group(1))
aW1wb3J0IHJlCgpiYXNlcyA9IFsnIi4uL21hdGxhYi9saWNlbnNlX2FkbWluLnBkZiIgYWJjICJ2ZnYiJywgJyJsaWNlbnNlX2FkbWluLnBkZiIgeHl6J10KZm9yIGJhc2UgaW4gYmFzZXM6CgltID0gcmUuc2VhcmNoKHInIiguKj9cLnBkZiknLCBiYXNlKQoJaWYgbToKCQlwcmludChtLmdyb3VwKDEpKQo=