Python: Add AST support for special operations.

These have the form `$name(arg1, arg2, ...)` and currently have no semantics.
They may be useful for testing purposes, however.

Author: tausbn

python/ql/src/semmle/python/AstGenerated.qll

@@ -1,3 +1,8 @@
+/*
+ *      This library file is auto-generated by 'semmle/query_gen.py'.
+ *      WARNING: Any modifications to this file will be lost.
+ *      Relations can be changed by modifying master.py.
+ */
 import python
 
 library class Add_ extends @py_Add, Operator {
@@ -1781,6 +1786,37 @@ library class Slice_ extends @py_Slice, Expr {
 
 }
 
+library class SpecialOperation_ extends @py_SpecialOperation, Expr {
+
+
+    /** Gets the name of this special operation. */
+    string getName() {
+        py_strs(result, this, 2)
+    }
+
+
+    /** Gets the arguments of this special operation. */
+    ExprList getArguments() {
+        py_expr_lists(result, this, 3)
+    }
+
+
+    /** Gets the nth argument of this special operation. */
+    Expr getArgument(int index) {
+        result = this.getArguments().getItem(index)
+    }
+
+    /** Gets an argument of this special operation. */
+    Expr getAnArgument() {
+        result = this.getArguments().getAnItem()
+    }
+
+    override string toString() {
+        result = "SpecialOperation"
+    }
+
+}
+
 library class Starred_ extends @py_Starred, Expr {