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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_insert(self, document):
 """Add an insert document to the list of ops. """

        validate_is_document_type("document", document)
        # Generate ObjectId client side.
        if not (isinstance(document, RawBSONDocument) or '_id' in document):
            document['_id'] = ObjectId()
        self.ops.append((_INSERT, document))