def _guessStringType(cls, data):
        """
        Guess the type of key in data.  The types map to _fromString_*
        methods.

        @type data: L{bytes}
        @param data: The key data.
        """
        if data.startswith(b'ssh-') or data.startswith(b'ecdsa-sha2-'):
            return 'public_openssh'
        elif data.startswith(b'-----BEGIN'):
            return 'private_openssh'
        elif data.startswith(b'{'):
            return 'public_lsh'
        elif data.startswith(b'('):
            return 'private_lsh'
        elif data.startswith(b'\x00\x00\x00\x07ssh-') or data.startswith(b'\x00\x00\x00\x13ecdsa-'):
            ignored, rest = common.getNS(data)
            count = 0
            while rest:
                count += 1
                ignored, rest = common.getMP(rest)
            if count > 4:
                return 'agentv3'
            else:
                return 'blob'

        Guess the type of key in data.  The types map to _fromString_*
        methods.

        @type data: L{bytes}
        @param data: The key data.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/ssh/keys.py