code: def vol_zone(poly1, poly2):
      volume of a zone defined by two polygon bases """
      c_point = central_p(poly1, poly2)
      c_point = (c_point[0], c_point[1], c_point[2])
      vol_therah = 0
      num = len(poly1)
      for i in range(num-2):
          # the upper part
          tehrahedron = [c_point, poly1[0], poly1[i+1], poly1[i+2]]
          vol_therah += vol_tehrahedron(tehrahedron)
          # the bottom part
          tehrahedron = [c_point, poly2[0], poly2[i+1], poly2[i+2]]
          vol_therah += vol_tehrahedron(tehrahedron)
      # the middle part
      for i in range(num-1):
          tehrahedron = [c_point, poly1[i], poly2[i], poly2[i+1]]
          vol_therah += vol_tehrahedron(tehrahedron)
          tehrahedron = [c_point, poly1[i], poly1[i+1], poly2[i]]
          vol_therah += vol_tehrahedron(tehrahedron)
      tehrahedron = [c_point, poly1[num-1], poly2[num-1], poly2[0]]
      vol_therah += vol_tehrahedron(tehrahedron)
      tehrahedron = [c_point, poly1[num-1], poly1[0], poly2[0]]
      vol_therah += vol_tehrahedron(tehrahedron)
      return vol_therah
docs: volume of a zone defined by two polygon bases