a method to retrieve the settings of an image

        :param image_name: string with name or id of image
        :param image_tag: [optional] string with tag associated with image 
        :return: dictionary of settings of image

        { TOO MANY TO LIST }

def inspect_image(self, image_name, image_tag=''):
        
        '''
            a method to retrieve the settings of an image

        :param image_name: string with name or id of image
        :param image_tag: [optional] string with tag associated with image 
        :return: dictionary of settings of image

        { TOO MANY TO LIST }
        '''

        title = '%s.inspect_image' % self.__class__.__name__

    # validate inputs
        input_fields = {
            'image_name': image_name,
            'image_tag': image_tag
        }
        for key, value in input_fields.items():
            if value:
                object_title = '%s(%s=%s)' % (title, key, str(value))
                self.fields.validate(value, '.%s' % key, object_title)

    # determine system command argument
        sys_arg = image_name
        if image_tag:
            sys_arg += ':%s' % image_tag

    # run inspect command
        import json
        sys_command = 'docker inspect %s' % sys_arg
        output_dict = json.loads(self.command(sys_command))
        image_settings = output_dict[0]

        return image_settings