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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 filter(self, field_name, field_value):
 """Add permanent filter on the collection :param field_name: name of the field to filter on :type field_name: str :param field_value: value to filter on :rtype: Collection """

        self.filters.append((field_name, field_value))
        return self