pem is a Python module for parsing and splitting of PEM files, i.e. Base64-encoded DER keys and certificates. It has no dependencies and does not attempt to interpret the certificate data in any way. It's born from the need to load keys, certificates, trust chains, and Diffie-Hellman parameters from various certificate deployments: some servers (like Apache) expect them to be a separate file, others (like nginx) expect them concatenated to the server certificate and finally some (like HAProxy) expect key, certificate, and chain to be in one file.