improve format

gui.py

@@ -1,20 +1,28 @@
 import matplotlib as mpl
-import matplotlib.pyplot as plt
-from matplotlib.widgets import Slider, Button, RadioButtons, LassoSelector
-from matplotlib.widgets import SpanSelector, PolygonSelector, CheckButtons
 import matplotlib.patches as patches
+import matplotlib.pyplot as plt
 from matplotlib.lines import Line2D
 from matplotlib.path import Path
+from matplotlib.widgets import (
+    Button,
+    CheckButtons,
+    LassoSelector,
+    PolygonSelector,
+    RadioButtons,
+    Slider,
+    SpanSelector,
+)
 from scipy.stats import linregress
-from postprocessor import *
 from skimage.draw import line
 
+from postprocessor import *
+
 
 class DraggablePoint:
 
     # http://stackoverflow.com/questions/21654008/matplotlib-drag-overlapping-points-interactively
 
-    lock = None  #  only one can be animated at a time
+    lock = None  # only one can be animated at a time
 
     def __init__(self, parent, x=0.1, y=0.1, size=0.1):