from openerp.osv import osv, fields

class theme_genesis(osv.Model):
    _inherit = 'product.template'
    
    _columns = {
        'x_product_image_1': fields.binary('Image #1'),
        'x_product_image_2': fields.binary('Image #2'),
        'x_product_image_3': fields.binary('Image #3'),
        'x_product_image_4': fields.binary('Image #4'),
        'x_product_image_5': fields.binary('Image #5'),
        'x_product_image_6': fields.binary('Image #6'),
        'x_product_image_7': fields.binary('Image #7'),
        'x_product_image_8': fields.binary('Image #8'),
        'x_product_image_9': fields.binary('Image #9'),
        'x_product_image_10': fields.binary('Image #10'),
        'x_product_image_11': fields.binary('Image #11'),
        'x_product_image_12': fields.binary('Image #12'),
        'x_product_image_13': fields.binary('Image #13'),
        'x_product_image_14': fields.binary('Image #14'),
        'x_product_image_15': fields.binary('Image #15'),
        'x_product_image_16': fields.binary('Image #16'),
        'x_product_image_17': fields.binary('Image #17'),
        'x_product_image_18': fields.binary('Image #18'),
        'x_product_image_19': fields.binary('Image #19'),
        'x_product_image_20': fields.binary('Image #20'),
        'x_product_image_21': fields.binary('Image #21'),
        'x_product_image_22': fields.binary('Image #22'),
        
    }

Create product_images.py