diff --git a/examples/howto/plot_batch_simulate.py b/examples/howto/plot_batch_simulate.py
index d6c378e65..35ac2a75c 100644
--- a/examples/howto/plot_batch_simulate.py
+++ b/examples/howto/plot_batch_simulate.py
@@ -107,10 +107,6 @@ def summary_func(results):
 ###############################################################################
 # Run the batch simulation and collect the results.
 
-# Uncomment this code if dask and distributed Python packages are installed.
-# from dask.distributed import Client
-# client = Client(threads_per_worker=1, n_workers=5, processes=False)
-
 
 # Initialize the network model and run the batch simulation.
 net = jones_2009_model(mesh_shape=(3, 3))
@@ -121,7 +117,7 @@ def summary_func(results):
                                           n_jobs=n_jobs,
                                           combinations=False,
                                           backend='loky')
-# backend='dask' if installed
+
 print("Simulation results:", simulation_results)
 ###############################################################################
 # This plot shows an overlay of all smoothed dipole waveforms from the
diff --git a/hnn_core/batch_simulate.py b/hnn_core/batch_simulate.py
index 9c09a5f88..168c3ea95 100644
--- a/hnn_core/batch_simulate.py
+++ b/hnn_core/batch_simulate.py
@@ -16,7 +16,7 @@
 
 
 class BatchSimulate(object):
-    def __init__(self, set_params, net=None,
+    def __init__(self, set_params, net=jones_2009_model(),
                  tstop=170, dt=0.025, n_trials=1,
                  save_folder='./sim_results', batch_size=100,
                  overwrite=True, save_outputs=False, save_dpl=True,
@@ -106,7 +106,7 @@ def __init__(self, set_params, net=None,
         will be overwritten.
         """
 
-        _validate_type(net, (Network, None), 'net', 'Network')
+        _validate_type(net, Network, 'net', 'Network')
         _validate_type(tstop, types='numeric', item_name='tstop')
         _validate_type(dt, types='numeric', item_name='dt')
         _validate_type(n_trials, types='int', item_name='n_trials')
@@ -129,7 +129,7 @@ def __init__(self, set_params, net=None,
         if summary_func is not None and not callable(summary_func):
             raise TypeError("summary_func must be a callable function")
 
-        self.net = net if net is not None else jones_2009_model()
+        self.net = net
         self.set_params = set_params
         self.tstop = tstop
         self.dt = dt