Recommendation on best cross-platform encryption package

[Malcolm Greene]

Is the cryptography package still considered the "best" cross-platform package for encrypting sensitive data being stored in files on disk. Use case: JSON data files containing potentially confidential/PII data using something along the lines of AES256 encryption. Goal is to encrypt data in memory before saving to disk and to read files into memory and decrypt from there using io.BytesIO streams.

Thank you,
Malcolm