docs: def _default_value_cell_data_func(self, tree_view_column, cell, model, iter, data=None):
          """Function set renderer properties for every single cell independently
  
          The function controls the editable and color scheme for every cell in the default value column according
          the use_runtime_value flag and whether the state is a library state.
  
          :param tree_view_column: the Gtk.TreeViewColumn to be rendered
          :param cell: the current CellRenderer
          :param model: the Gtk.ListStore or TreeStore that is the model for TreeView
          :param iter: an iterator over the rows of the TreeStore/Gtk.ListStore Model
          :param data: optional data to be passed: see http://dumbmatter.com/2012/02/some-notes-on-porting-from-pygtk-to-pygobject/
          """
          if isinstance(self.model.state, LibraryState):
              use_runtime_value = model.get_value(iter, self.USE_RUNTIME_VALUE_STORAGE_ID)
              if use_runtime_value:
                  cell.set_property("editable", True)
                  cell.set_property('text', model.get_value(iter, self.RUNTIME_VALUE_STORAGE_ID))
                  cell.set_property('foreground', "white")
              else:
                  cell.set_property("editable", False)
                  cell.set_property('text', model.get_value(iter, self.DEFAULT_VALUE_STORAGE_ID))
                  cell.set_property('foreground', "dark grey")
  
          return