a method to list the local docker images
            
        :return: list of dictionaries with available image fields

        [ {
            'CREATED': '7 days ago',
            'TAG': 'latest',
            'IMAGE ID': '2298fbaac143',
            'VIRTUAL SIZE': '302.7 MB',
            'REPOSITORY': 'test1'
        } ]

def images(self):

        '''
            a method to list the local docker images
            
        :return: list of dictionaries with available image fields

        [ {
            'CREATED': '7 days ago',
            'TAG': 'latest',
            'IMAGE ID': '2298fbaac143',
            'VIRTUAL SIZE': '302.7 MB',
            'REPOSITORY': 'test1'
        } ]
        '''

        sys_command = 'docker images'
        sys_output = self.command(sys_command)
        image_list = self._images(sys_output)

        return image_list