GDS Cad integration error

[aj56]

from gdsCAD.core import Layout
from gdsCAD.Class_Wafer_Style import Wafer_Style_4_inch

from gdsCAD import Cell38

list = []
list.append(Cell38)

Wafer_GridStyle = Wafer_Style_4_inch('Wafer_GridStyle', list)
layout_wafer_1 = Layout('layout_wafer_final')
layout_wafer_1.add(Wafer_GridStyle)
layout_wafer_1.save('mask_final_revised_2.gds')

Output Screen:
If 2700 is not equal to 2700 there will be a rounding (machine accuracy) problem with the triangles.
If 2700 is not equal to 2700 there will be a rounding (machine accuracy) problem with the triangles.
If 2700 is not equal to 2700 there will be a rounding (machine accuracy) problem with the triangles.
If 2700 is not equal to 2700 there will be a rounding (machine accuracy) problem with the triangles.
If 2700 is not equal to 2700 there will be a rounding (machine accuracy) problem with the triangles.
If 2700 is not equal to 2700 there will be a rounding (machine accuracy) problem with the triangles.
Writing the following cells
('cell_38:', <gdsCAD.core.Cell object at 0x110ba3450>)

TypeError Traceback (most recent call last)
in ()
14
15
---> 16 Wafer_GridStyle = Wafer_Style_4_inch('Wafer_GridStyle', list)
17
18 layout_wafer_1 = Layout('layout_wafer_final')

/usr/local/lib/python2.7/site-packages/gdsCAD/Class_Wafer_Style.pyc in init(self, name, cells, block_gap, *args, **kwargs)
43 'LOWER LEFT':(-3.05e4,-2.2e4), 'LOWER RIGHT':(3.025e4,-2.15e4)}
44
---> 45 Wafer_GridStyle.init(self, name, cells, block_gap, *args, **kwargs)
46
47 self._place_blocks()

/usr/local/lib/python2.7/site-packages/gdsCAD/templates.pyc in init(self, name, cells, block_gap)
54 #self.cells = Cell
55 self.cells = cells
---> 56 self.cell_layers=self._cell_layers()
57 self._label=None
58

/usr/local/lib/python2.7/site-packages/gdsCAD/templates.pyc in _cell_layers(self)
68 cell_layers |= set(c.get_layers())
69 else:
---> 70 for s in c:
71 cell_layers |= set(s.get_layers())
72 return list(cell_layers)

TypeError: 'module' object is not iterable

[aj56]

This gives an error of module object not iterable.