klippy: Remove some obscure python2 dependencies

Don't modify dictionaries while iterating them and be careful to use
// when doing an integer divide.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/gcode.py

@@ -40,7 +40,7 @@ class GCodeParser:
             handlers = [h for h in handlers
                         if getattr(self, 'cmd_'+h+'_when_not_ready', False)]
         gcode_handlers = { h: getattr(self, 'cmd_'+h) for h in handlers }
-        for h, f in gcode_handlers.items():
+        for h, f in list(gcode_handlers.items()):
             aliases = getattr(self, 'cmd_'+h+'_aliases', [])
             gcode_handlers.update({ a: f for a in aliases })
         return gcode_handlers

klippy/msgproto.py

@@ -252,7 +252,7 @@ class MessageParser:
     def _parse_buffer(self, value):
         tval = int(value, 16)
         out = []
-        for i in range(len(value)/2):
+        for i in range(len(value) // 2):
             out.append(tval & 0xff)
             tval >>= 8
         out.reverse()

klippy/stepper.py

@@ -36,7 +36,7 @@ class PrinterStepper:
             else:
                 self.homing_endstop_accuracy = int(math.ceil(
                     endstop_accuracy * self.inv_step_dist))
-            if self.homing_endstop_accuracy >= self.homing_stepper_phases/2:
+            if self.homing_endstop_accuracy >= self.homing_stepper_phases // 2:
                 logging.info("Endstop for %s is not accurate enough for stepper"
                              " phase adjustment" % (name,))
                 self.homing_stepper_phases = None