diff --git a/imsim/sky_model.py b/imsim/sky_model.py
index a962548d..8560bc28 100644
--- a/imsim/sky_model.py
+++ b/imsim/sky_model.py
@@ -3,7 +3,6 @@
 import warnings
 import numpy as np
 import galsim
-import pickle
 from galsim.config import InputLoader, RegisterInputType, RegisterValueType
 from scipy.interpolate import RegularGridInterpolator, RectBivariateSpline
 import os
@@ -120,6 +119,7 @@ def __call__(self, x, y):
         """
         return (self.a*x + self.b*y + self.c)/self.sky_level_center
 
+
 class CCD_Fringing:
     """
     Class generates normalized fringing map.
@@ -172,7 +172,6 @@ def generate_heightfield(self, fractal_dimension=2.5, n=4096):
 
         return np.fft.ifft2(A)
 
-
     def simulate_fringes(self, amp=0.002):
         '''
         # Generate random fringing pattern from a heightfield
@@ -191,7 +190,6 @@ def simulate_fringes(self, amp=0.002):
         #Z  += 1
         return(Z)
 
-
     def fringe_variation_level(self):
         '''
         Function implementing temporal and spatial variation of fringing.
@@ -245,6 +243,7 @@ def calculate_fringe_amplitude(self,x,y,amplitude = 0.002):
 
         return (interp_func((x,y)))
 
+
 class SkyModelLoader(InputLoader):
     """
     Class to load a SkyModel object.