The manual review happened because your snap has files with an executable stack. From the review:
“Found files with executable stack. This adds PROT_EXEC to mmap(2) during mediation which may cause security denials. Either adjust your program to not require an executable stack, strip it with ‘execstack --clear-execstack …’ or remove the affected file from your snap. Affected files: lib/python3.5/site-packages/nassl/_nassl.cpython-35m-x86_64-linux-gnu.so, lib/python3.5/site-packages/nassl/_nassl_legacy.cpython-35m-x86_64-linux-gnu.so”
I’ve approved all of these, but please see Snap and executable stacks for how to make your snap pass automated review.