Fixes issue 1571:

Adding missing close for open.
If the "close()" call is missing after a "open(filename)" call, the filename isn't guaranteed to be closed before the interpreter exits.
This is generally a bad practice as explained here: https://stackoverflow.com/questions/7395542/is-explicitly-closing-files-important

Also replaced "fid=open(filename) fid.close()" statements for files with the safer
"with open(filename) as fid:" blocks. See https://www.python.org/dev/peps/pep-0343/

samples/doodle/superdoodle.py

@@ -76,21 +76,17 @@ class DoodleFrame(wx.Frame):
         # size events using this sizer.
         self.SetSizer(box)
 
-
     def SaveFile(self):
         if self.filename:
             data = self.doodle.GetLinesData()
-            f = open(self.filename, 'wb')
-            pickle.dump(data, f)
-            f.close()
-
+            with open(self.filename, 'wb') as f:
+                pickle.dump(data, f)
 
     def ReadFile(self):
         if self.filename:
             try:
-                f = open(self.filename, 'rb')
-                data = pickle.load(f)
-                f.close()
+                with open(self.filename, 'rb') as f:
+                    data = pickle.load(f)
                 self.doodle.SetLinesData(data)
             except pickle.UnpicklingError:
                 wx.MessageBox("%s is not a doodle file." % self.filename,

samples/floatcanvas/Animation.py

@@ -258,9 +258,8 @@ def Read_MapGen(filename,stats = False):
 
     """
     from numpy import array
-    file = open(filename,'rt')
-    data = file.readlines()
-    data = [s.strip() for s in data]
+    with open(filename,'rt') as file_:
+        data = [s.strip() for s in file_.readlines()]
 
     Shorelines = []
     segment = []
@@ -279,21 +278,11 @@ def Read_MapGen(filename,stats = False):
             NumPoints = NumPoints + len(segment)
         AvgPoints = NumPoints / NumSegments
         print("Number of Segments: ", NumSegments)
-        print("Average Number of Points per segment: ",AvgPoints)
+        print("Average Number of Points per segment: ", AvgPoints)
 
     return Shorelines
 
-if __name__ == "__main__":
 
+if __name__ == "__main__":
     app = DemoApp(0)
     app.MainLoop()
-
-
-
-
-
-
-
-
-
-

samples/floatcanvas/BNAEditor.py

@@ -50,37 +50,36 @@ class BNAData:
     def Save(self, filename = None):
         if not filename:
             filename = self.filename
-        file = open(filename, 'w')
-        for i, points in enumerate(self.PointsData):
-            file.write('"%s","%s", %i\n'%(self.Names[i],self.Types[i],len(points) ) )
-            for p in points:
-                file.write("%.12f,%.12f\n"%(tuple(p)))
+        with open(filename, 'w') as file:
+            for i, points in enumerate(self.PointsData):
+                file.write('"%s","%s", %i\n'%(self.Names[i],self.Types[i],len(points) ) )
+                for p in points:
+                    file.write("%.12f,%.12f\n"%(tuple(p)))
 
     def Load(self, filename):
         #print("Loading:", filename)
-        file = open(filename,'rU')
 
         self.Filename = filename
         self.PointsData = []
         self.Names = []
         self.Types = []
-        while 1:
-            line = file.readline()
-            if not line:
-                break
-            line = line.strip()
-            Name, line = line.split('","')
-            Name = Name[1:]
-            Type,line = line.split('",')
-            num_points = int(line)
-            self.Types.append(Type)
-            self.Names.append(Name)
-            polygon = N.zeros((num_points,2),N.float)
-            for i in range(num_points):
-                polygon[i,:] = map(float, file.readline().split(','))
-            self.PointsData.append(polygon)
 
-        file.close()
+        with open(filename,'rU') as file_:
+            for line in file_:
+                if not line:
+                    break
+                line = line.strip()
+                Name, line = line.split('","')
+                Name = Name[1:]
+                Type,line = line.split('",')
+                num_points = int(line)
+                self.Types.append(Type)
+                self.Names.append(Name)
+                polygon = N.zeros((num_points,2),N.float)
+                for i in range(num_points):
+                    polygon[i,:] = map(float, file_.readline().split(','))
+                self.PointsData.append(polygon)
+
         return None
 
 class DrawFrame(wx.Frame):

samples/printing/printing.py

@@ -115,7 +115,8 @@ class PrintFrameworkSample(wx.Frame):
         self.tc.SetFont(wx.Font(FONTSIZE, wx.FONTFAMILY_TELETYPE,
                                 wx.FONTSTYLE_NORMAL, wx.FONTWEIGHT_NORMAL))
         filename = os.path.join(os.path.dirname(__file__), "sample-text.txt")
-        self.tc.SetValue(open(filename).read())
+        with open(filename) as fid:
+            self.tc.SetValue(fid.read())
         self.tc.Bind(wx.EVT_SET_FOCUS, self.OnClearSelection)
         wx.CallAfter(self.tc.SetInsertionPoint, 0)