def __init__(self, checksum, seq_num):
self.version = b"<STR_LIT>"<EOL>self.checksum = checksum<EOL>self.seq_num = seq_num<EOL>
[MS-NLMP] v28.0 2016-07-14

2.2.2.9.2 NTLMSSP_MESSAGE_SIGNATURE for Extended Session Security
This version of the NTLMSSP_MESSAGE_SIGNATURE structure MUST be used
when the NTLMSSP_NEGOTIATE_EXTENDED_SESSIONSECURITY flag is negotiated

:param checksum: An 8-byte array that contains the checksum for the
    message
:param seq_num: A 32-bit unsigned integer that contains the NTLM
    sequence number for this application message