diff --git a/mrdna/readers/segmentmodel_from_lists.py b/mrdna/readers/segmentmodel_from_lists.py
index 3f96df780c4227f4e4b4120f3decd59fd80c1875..7e65b97b3a54b0dc72a558785cf2406fd247134d 100644
--- a/mrdna/readers/segmentmodel_from_lists.py
+++ b/mrdna/readers/segmentmodel_from_lists.py
@@ -234,7 +234,7 @@ def model_from_basepair_stack_3prime(coordinate, basepair, stack, three_prime,
                                      max_basepairs_per_bead = 5,
                                      max_nucleotides_per_bead = 5,
                                      local_twist = False,
-                                     dimensions=(5000,5000,5000)
+                                     dimensions=(5000,5000,5000),
                                      **model_parameters):
     """ 
     Creates a SegmentModel object from lists of each nucleotide's
@@ -486,7 +486,7 @@ def model_from_pandas(df,coordinate_col="r",bp_col="bp",stack_col="stack",three_
                         max_nucleotides_per_bead = 5,
                         local_twist = False,
                         dimensions=(5000,5000,5000)
-                        **model_parameters):
+                        ,**model_parameters):
     try:
         c=df[coordinate_col]
     except:
@@ -527,7 +527,7 @@ def model_from_pandas(df,coordinate_col="r",bp_col="bp",stack_col="stack",three_
                                         max_basepairs_per_bead = max_basepairs_per_bead,
                                         max_nucleotides_per_bead =max_nucleotides_per_bead ,
                                         local_twist = local_twist,
-                                        dimensions=dimensions
+                                        dimensions=dimensions,
                                         **model_parameters)
         return model
     except: