Python 3 fix: autodock_plugin list sorting

Fixes #110

Author: speleo3

plugins/autodock_plugin.py

@@ -2533,7 +2533,7 @@ def load_dlg(self, filename):
             model.name = name
             pose_list.append(model)
 
-        pose_list.sort(lambda a, b: cmp(a.energy, b.energy))
+        pose_list.sort(key=lambda a: a.energy)
         self.pose_viewer_ligand_dic[name] = {}
         for i in range(len(pose_list)):
             pose_list[i].poseN = i + 1
@@ -2562,7 +2562,7 @@ def load_pdbqt(self, filename):
 #            print model.energy
             pose_list.append(model)
            # print 'done pose list'
-        pose_list.sort(lambda a, b: cmp(a.energy, b.energy))
+        pose_list.sort(key=lambda a: a.energy)
 
         self.pose_viewer_ligand_dic[name] = {}
         for i in range(len(pose_list)):
@@ -2579,7 +2579,7 @@ def update_combo(self, name):
         self.pose_viewer_ligand_pages[name] = {'name': self.pose_viewer_notebook.add(name)}
         pose_list = list(self.pose_viewer_ligand_dic[name].keys())
 
-        pose_list.sort(lambda a, b: cmp(int(a.split('::')[1]), int(b.split('::')[1])))
+        pose_list.sort(key=lambda a: int(a.split('::')[1]))
         self.pose_viewer_ligand_pages[name].update({'poses': pose_list})
 
         self.pose_viewer_buttonbox = Pmw.ButtonBox(self.pose_viewer_ligand_pages[name]['name'], padx=3)
@@ -2676,7 +2676,7 @@ def make_complete_ligand_list(self):
         self.sort_complete_ligand_list()
 
     def sort_complete_ligand_list(self):
-        self.all_ligands.sort(lambda a, b: cmp(a.energy, b.energy))
+        self.all_ligands.sort(key=lambda a: a.energy)
 
     def select_best_poses(self):
         self.sort_complete_ligand_list()