human
Complete this python program:
def eliot_to_stdout(message_formats, action_formats, stdout=sys.stdout):
assistant
#Here is the Python program you requested.

    """Write pretty versions of eliot log messages to stdout.
    """
    def eliot_output(message):
        message_type = message.get('message_type')
        action_type = message.get('action_type')
        action_status = message.get('action_status')
        message_format = ''
        if (message_type is not None):
            if ((message_type == 'twisted:log') and message.get('error')):
                message_format = '%(message)s'
            else:
                message_format = message_formats.get(message_type, '')
        elif (action_type is not None):
            if (action_status == 'started'):
                message_format = action_formats.get('action_type', '')
        stdout.write((message_format % message))
        stdout.flush()
    add_destination(eliot_output)