diff --git a/rmgpy/constraints.py b/rmgpy/constraints.py
index d00d1ca43bf..be7f950f4ce 100644
--- a/rmgpy/constraints.py
+++ b/rmgpy/constraints.py
@@ -31,6 +31,7 @@
 
 from rmgpy.species import Species
 
+
 def pass_cutting_threshold(species):
     """
     Pass in either a `Species` or `Molecule` object and checks whether it passes 
@@ -58,6 +59,7 @@ def pass_cutting_threshold(species):
 
     return False
 
+
 def fails_species_constraints(species):
     """
     Pass in either a `Species` or `Molecule` object and checks whether it passes