I fixed some minor issues and assumed some value parameters to test your code. 

    from osgeo import gdal, osr
    import numpy as np
    
    raster_classified = 'c:/Users/Usuario/pyqgis_data/raster_classified.tif'
    
    col = 20 
    row = 20
    
    cell_size = 0.003
    origin_x = 10000
    origin_y = 10000
    
    driver = gdal.GetDriverByName('GTiff')
    
    outRaster = driver.Create(raster_classified, col, row, 1, gdal.GDT_Int16)
    
    outband = outRaster.GetRasterBand(1)
    
    outRaster.SetGeoTransform((origin_x, 
                               cell_size, 
                               0, 
                               origin_y  - (cell_size * row), 
                               0, 
                               cell_size))
    
    values = [ [] for i in range(row) ]
    
    for i in range(row):
        for j in range(col):
                values[i].append(1)
    
    outras_array = np.array(values)
    
    outband.WriteArray(outras_array)
    outRasterSRS = osr.SpatialReference()
    outRasterSRS.ImportFromEPSG(4326)
    outRaster.SetProjection(outRasterSRS.ExportToWkt())
    outRaster = None

After running it at the Python Console of QGIS, I got a 20x20 *.tif raster (all pixels equal 1); as it can be seen at next image:

[![enter image description here][1]][1]

It worked.

  [1]: https://i.sstatic.net/sIPEy.png