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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def write(self, buffer):
 """Write a string to the socket, doubling any IAC characters. Can block if the connection is blocked. May raise socket.error if the connection is closed. """

        if type(buffer) == type(0):
            buffer = chr(buffer)
        elif not isinstance(buffer, bytes):
            buffer = buffer.encode(self.encoding)
        if IAC in buffer:
            buffer = buffer.replace(IAC, IAC+IAC)
        self.msg("send %s", repr(buffer))
        self.sock.send(buffer)