def create_image(self, instance_id, name,
                     description=None, no_reboot=False):
        """
        Will create an AMI from the instance in the running or stopped
        state.

        :type instance_id: string
        :param instance_id: the ID of the instance to image.

        :type name: string
        :param name: The name of the new image

        :type description: string
        :param description: An optional human-readable string describing
                            the contents and purpose of the AMI.

        :type no_reboot: bool
        :param no_reboot: An optional flag indicating that the bundling process
                          should not attempt to shutdown the instance before
                          bundling.  If this flag is True, the responsibility
                          of maintaining file system integrity is left to the
                          owner of the instance.

        :rtype: string
        :return: The new image id
        """
        params = {'InstanceId' : instance_id,
                  'Name' : name}
        if description:
            params['Description'] = description
        if no_reboot:
            params['NoReboot'] = 'true'
        img = self.get_object('CreateImage', params, Image, verb='POST')
        return img.id
Will create an AMI from the instance in the running or stopped
        state.

        :type instance_id: string
        :param instance_id: the ID of the instance to image.

        :type name: string
        :param name: The name of the new image

        :type description: string
        :param description: An optional human-readable string describing
                            the contents and purpose of the AMI.

        :type no_reboot: bool
        :param no_reboot: An optional flag indicating that the bundling process
                          should not attempt to shutdown the instance before
                          bundling.  If this flag is True, the responsibility
                          of maintaining file system integrity is left to the
                          owner of the instance.

        :rtype: string
        :return: The new image id