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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 serialize(self):
 """ Return a string representing the subview with all of its filter criteria. Returns: str: String with subview definition. """

        lines = []

        for criterion in self.filter_criteria:
            lines.append(criterion.name())
            lines.append(criterion.serialize())

        return '\n'.join(lines)