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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def extract(self, cell):
 """ Extract a cell from the this GDSII file and include it in the current global library, including referenced dependencies. Parameters cell : ``Cell`` or string Cell or name of the cell to be extracted from the imported file. Referenced cells will be automatically extracted as well. Returns ------- out : ``Cell`` The extracted cell. """

        cell = self.cell_dict.get(cell, cell)
        current_library.add(cell)
        current_library.add(cell.get_dependencies(True))
        return cell