def count(self, column=None):
        "Counts the total number of 'non-null' cells in the given column."
        if column is None:
            return len(self.__data_area)
        data_type, index = self.__columns[column]
        null, total = data_type(), 0
        for row in self.__data_area.values():
            if row[index] != null:
                total += 1
        return total
Counts the total number of 'non-null' cells in the given column.
recipes/Python/577825_Rudimentary_Database_Engine/recipe-577825.py