the usage of CertAuth.py is pretty easy to understand but in case of doubt running

"python3 CertAuth.py -h" will give a good understanding of its usage

output of the above is as follows:
>
	usage: python3 CertAuth.py <path for backup private key> <CA public certificate> <subject public certificate> <password for backup private key>

	Sample : python3 CertAuth.py cert_bckup.p12 root.crt subject.crt CSE539_Rocks!

	positional arguments:
	  arguments   includes file paths and passwords needed for successful
	              execution

	optional arguments:
	  -h, --help  show this help message and exit
>

the python program makes use of both libraries - cryptography and pyOpenSSL

To run our program, simply run:
python3 CertAuth.py p12Filepath rootFilepath subjectFilepath password
where p12Filepath is the path to a .p12 file containing the subject's private key,
rootFilepath is the path to a root's certificate file,
subjectFilepath is the path to a subject's certificate file,
and password is the password to the p12 file.