Trailing comma in use list
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<?php
function() use($a,) {};
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array(
    0: Stmt_Expression(
        expr: Expr_Closure(
            attrGroups: array(
            )
            static: false
            byRef: false
            params: array(
            )
            uses: array(
                0: ClosureUse(
                    var: Expr_Variable(
                        name: a
                    )
                    byRef: false
                )
            )
            returnType: null
            stmts: array(
            )
        )
    )
)