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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 get_dependencies(self, recursive=False):
 """ Returns a list of the cells included in this cell as references. Parameters recursive : bool If True returns cascading dependencies. Returns ------- out : set of ``Cell`` List of the cells referenced by this cell. """

        dependencies = set()
        for element in self.elements:
            if isinstance(element, CellReference) or isinstance(
                    element, CellArray):
                if recursive:
                    dependencies.update(
                        element.ref_cell.get_dependencies(True))
                dependencies.add(element.ref_cell)
        return dependencies