PyExpression () { final PyNamedParameterStub stub = getStub(); if (stub != null && stub.getDefaultValueText() == null) { return null; } final ASTNode[] nodes = getNode().getChildren(PythonDialectsTokenSetProvider.getInstance().getExpressionTokens()); if (nodes.length > 0) { return (PyExpression)nodes[0].getPsi(); } return null; }