diff --git a/pySDC/helpers/fieldsIO.py b/pySDC/helpers/fieldsIO.py
index d7b32d980..732933117 100644
--- a/pySDC/helpers/fieldsIO.py
+++ b/pySDC/helpers/fieldsIO.py
@@ -43,15 +43,18 @@
 import numpy as np
 from typing import Type, TypeVar
 
+T = TypeVar("T")
+
 try:
     from mpi4py import MPI
 except ImportError:
 
     class MPI:
         COMM_WORLD = None
+        Intracomm = T
+
 
 
-T = TypeVar("T")
 
 # Supported data types
 DTYPES = {