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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 area(self, by_spec=False):
 """ Calculate the total area of the elements on this cell, including cell references and arrays. Parameters by_spec : bool If ``True``, the return value is a dictionary with the areas of each individual pair (layer, datatype). Returns ------- out : number, dictionary Area of this cell. """

        if by_spec:
            cell_area = {}
            for element in self.elements:
                element_area = element.area(True)
                for ll in element_area.keys():
                    if ll in cell_area:
                        cell_area[ll] += element_area[ll]
                    else:
                        cell_area[ll] = element_area[ll]
        else:
            cell_area = 0
            for element in self.elements:
                cell_area += element.area()
        return cell_area