Python: Fix false positive for cyclic imports guarded by if False:.

python/ql/src/Imports/Cyclic.qll

@@ -22,7 +22,8 @@ predicate circular_import(ModuleValue m1, ModuleValue m2) {
 ModuleValue stmt_imports(ImportingStmt s) {
     exists(string name |
         result.importedAs(name) and not name = "__main__" |
-        name = s.getAnImportedModuleName()
+        name = s.getAnImportedModuleName() and
+        s.getASubExpression().pointsTo(result)
     )
 }