contract A {
	int public testvar;
	function foo() internal returns (uint256);
	function test(uint8 _a) internal returns (uint256);
}
contract B {
	function foo() internal returns (uint256);
	function test() internal returns (uint256);
}
contract C {
	function foo() internal returns (uint256);
}
contract D {
	function foo() internal returns (uint256);
}
contract X is A, B, C, D {
	int public override testvar;
	function test() internal override returns (uint256);
	function foo() internal override(A, B, C, D) returns (uint256);
}
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