from sectionproperties.pre import Geometry

concrete = None  # define your concrete material properties here

pts = [
  (0, 0), (600, 0), (600, 800), (0, 800), (100, 100), (500, 100), (500, 700),
  (100, 700)
]
fcts = [(0, 1), (1, 2), (2, 3), (3, 0), (4, 5), (5, 6), (6, 7), (7, 0)]
cps = [(50, 50)]
hls = [(400, 400)]

geom = Geometry.from_points(
  points=pts, facets=fcts, control_points=cps, holes=hls, material=concrete
)
geom.plot_geometry()