How to generate the PEM serialization for the public RSA/DSA key

Question

Using PyCrypto I was able to generate the public and private PEM serialization for a RSA key, but in PyCrypto the DSA class has no exportKey() method.

Trying PyOpenSSL I was able to generate the private PEM serialization for RSA and DSA keys, bu there is no crypto.dump_publickey method in PyOpenSSL.

I am looking for suggestion of how to generate the PEM serialization for RSA and DSA keys.

Many thanks!

PS: meanwhile I have changed the PyOpenSSL code to also export an dump_privatekey method for crypto API. PyOpenSSL bug and patch can be found at: https://bugs.launchpad.net/pyopenssl/+bug/780089

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I was already using Twisted.conch so I solved this problem by manually generating a DSA/RSA key using PyCrypto and then initializing a twisted.conch.ssh.key.Key using this key. The Key class from Conch provides a toString method for string serialization.