[pygtk] Line wrapping in TreeView while editing

[saeed]

There is two properties of CellRendererText: "wrap-mode" and
"wrap-width", but it doesn't work while editing.
for example:
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cell = gtk.CellRendererText()
cell.set_property('wrap-mode', gtk.WRAP_WORD)
cell.set_property('editable', True)
col = gtk.TreeViewColumn('Description', cell, text=0)
col.set_resizable(True)
treeview.append_column(col)
treeview.connect('expose-event', treeviewExpose, cell, col)

def treeviewExpose(widget, event, cell, col):
   cell.set_property('wrap-width', col.get_width())
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