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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 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