def __init__(self, content=None):
if content is not None:<EOL><INDENT>self.packet = BytesIO(content)<EOL><DEDENT>else:<EOL><INDENT>self.packet = BytesIO()<EOL><DEDENT>
Create a new SSH2 message.

:param str content:
    the byte stream to use as the message content (passed in only when
    decomposing a message).