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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(self, entry, local_file):
 """Add a metadata row."""

        row = self.rowClass()

        for key, val in entry.items():
            if key in self.columns:
                setattr(row, key, val)

        row.local_filename = os.path.join('.', os.path.relpath(local_file))

        self.rows.append(row)