def send_header(self, keyword, value):
        """Send a MIME header."""
        if self.request_version != 'HTTP/0.9':
            self.wfile.write("%s: %s\r\n" % (keyword, value))

        if keyword.lower() == 'connection':
            if value.lower() == 'close':
                self.close_connection = 1
            elif value.lower() == 'keep-alive':
                self.close_connection = 0
Send a MIME header.