M2Crypto convert key from PEM to DER ?

Hi -

I'd like to use M2Crypto to to convert a server key from PEM format to 
DER. Specifically, I'd like to replace the following openssl command:

*openssl rsa –in input.key –inform PEM –out output.key –outform DER

I think I understand how to do something similar with the certs, but 
haven't figured out how to do this with just the private key. I'm sure 
I'm missing something; can anyone provide any tips?

Thanks in advance -

Hans
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