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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 __to_browser(self, message_no):
 """ Write a single message to file and open the file in a browser """

        filename = self.__to_file(message_no)
        try:
            command = self.config.get('General', 'browser_command')
        except (ConfigParser.NoOptionError, AttributeError):
            print 'Incorrect or missing .ini file. See --help.'
            sys.exit(5)
        command = str(command).format(filename)
        command_list = command.split(' ')
        try:
            subprocess.Popen(command_list, stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE)
        except OSError:
            print 'Unable to execute the browsercommand:'
            print command
            print 'Exiting!'
            sys.exit(21)