void (@NotNull ASTNode child) { PyExpression left = getLeftExpression(); PyExpression right = getRightExpression(); if (left == child.getPsi() && right != null) { replace(right); } else if (right == child.getPsi() && left != null) { replace(left); } else { throw new IncorrectOperationException("Element " + child.getPsi() + " is neither left expression or right expression"); } }