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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 add_column(self, column):
 """Add a new column along with a formatting function."""

        self.columns.append(column.name)
        self.column_funcs.append(column.path)

        if column.mask is not None:
            self.mask_parts.add(column.mask)