The load_dh_params() method of SSLContext does not properly handle unicode filenames on Windows (like load_verify_location() does).

It should convert any passed unicode path to the filesystem encoding.

This is already fixed in the 3.x head revision, by loading the file via python instead of the OpenSSL BIO functions, but is broken in 2.7.10.

Currently it silently works for most files due to an implicit conversion to string, but with the wrong default encoding instead of filesystem encoding.