[[x1,y1],[x2,y2],[x3,y3],[x4,y4]]   [[x5,y5],[x6,y6],[x7,y7].[x8,y8]]

feature = QgsFeature()
feature.setGeometry(QgsGeometry.fromMultiPolygon([polygon_points]))

TypeError: QgsGeometry.fromMultiPolygon(): argument 1 has unexpected type 'list'

read_polygon=open('shapes_point.txt','rb')
polygons=[]
polygon_lines=read_polygon.readlines()  #read all polygons
for line in polygon_lines:              #read per polygon in polygons
  for points in line:                   #read per point in polygon
        x=points[0]
        y=points[1]
        Qgs_point=QgsPoint(float(x),float(y))
        polygons.append(Qgs_point)
feature = QgsFeature()
feature.setGeometry(QgsGeometry.fromMultiPolygon((QgsGeometry.fromMultiPolygon([polygons for polygon in polygons]))))

feature = QgsFeature()
feature.setGeometry(QgsGeometry.Polygon([polygon_points]))

[ # The list of polygons
 [ # The list of rings for the first polygon
  [ # The list of QgsCoordinates
    QgsPoint(0,0), QgsPoint(1,0), QgsPoint(0,1)
  ]
 ],
 [ # The list of rings for the second polygon
  [ # The list of QgsCoordinates for the first polygon
    QgsPoint(2,2), QgsPoint(3,2), QgsPoint(2,3)
  ]
 ]
]

[[[QgsPoint(point[0],point[1]) for point in polygon ] for polygon in polygon_points ]]

feature.setGeometry(QgsGeometry.fromMultiPolygon([[[QgsPoint(point[0],point[1]) for point in polygon ] for polygon in polygon_points ]]))