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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 get_compiler(self, using=None, connection=None):
 """ Overrides the Query method get_compiler in order to return an instance of the above custom compiler. """

        # Copy the body of this method from Django except the final
        # return statement. We will ignore code coverage for this.
        if using is None and connection is None:  # pragma: no cover
            raise ValueError("Need either using or connection")
        if using:
            connection = connections[using]
        # Check that the compiler will be able to execute the query
        for alias, aggregate in self.annotation_select.items():
            connection.ops.check_expression_support(aggregate)
        # Instantiate the custom compiler.
        return {
            CTEUpdateQuery: CTEUpdateQueryCompiler,
            CTEInsertQuery: CTEInsertQueryCompiler,
            CTEDeleteQuery: CTEDeleteQueryCompiler,
            CTEAggregateQuery: CTEAggregateQueryCompiler,
        }.get(self.__class__, CTEQueryCompiler)(self, connection, using)