From Fedora Project Wiki

Python NSS Bindings

Python bindings for NSS/NSPR allow Python programs to utilize the NSS cryptographic libraries for SSL/TLS and PKI certificate management. The python-nss package provides a Python binding to the NSS and NSPR support libraries.

Network Security Services (NSS) is a set of libraries supporting security-enabled client and server applications. Applications built with NSS can support SSL v2 and v3, TLS, PKCS #5, PKCS #7, PKCS #11, PKCS #12, S/MIME, X.509 v3 certificates and other security standards. NSS has received FIPS 140 validation from NIST.