@staticmethod<EOL><INDENT>def generate(bits, progress_func=None):<DEDENT>
key = rsa.generate_private_key(<EOL>public_exponent=<NUM_LIT>, key_size=bits, backend=default_backend()<EOL>)<EOL>return RSAKey(key=key)<EOL>
Generate a new private RSA key.  This factory function can be used to
generate a new host key or authentication key.

:param int bits: number of bits the generated key should be.
:param progress_func: Unused
:return: new `.RSAKey` private key