Fix header inclusion

.gitignore

@@ -74,3 +74,4 @@ CMakeDefs.h
 /walberla-config.cmake
 /cmake-build-debug/
 /cmake-build-release/
+/cmake-build-debug-remote/

python/pystencils_walberla/kernel_selection.py

@@ -236,7 +236,7 @@ class KernelFamily:
         return self._ast_attrs[name]
 
     def get_headers(self):
-        all_headers = [get_headers(ast) for ast in self.all_asts]
+        all_headers = [list(get_headers(ast)) for ast in self.all_asts]
         return reduce(merge_sorted_lists, all_headers)
 
     def generate_kernel_invocation_code(self, **kwargs):