PJSIP Upgrade Issue

Am upgrading an old channel based Asterisk to 18 which means the pjsip migration
When running the sip_to_pjsql.py file here —> asterisk/contrib/scripts/sip_to_pjsip at master · asterisk/asterisk · GitHub
I am getting the below

Please, report any issue at:
https://issues.asterisk.org/
Reading sip.conf
Converting to PJSIP realtime sql…
Writing pjsip.sql
Traceback (most recent call last):
File “/tmp/pjsipnew/sip_to_pjsql.py”, line 79, in
write_pjsip(pjsip_filename, pjsip, non_mappings)
File “/tmp/pjsipnew/sip_to_pjsql.py”, line 17, in write_pjsip
pjsip.write(fp)
File “/tmp/pjsipnew/sqlconfigparser.py”, line 72, in write
print(“Could not open file " + config_file + " for writing”)
TypeError: cannot concatenate ‘str’ and ‘file’ objects