getting ready for Python 3 (#619)

* tabs to spaces
python 2 to 3: https://portingguide.readthedocs.io/en/latest/syntax.html#tabs-and-spaces

* use the new except syntax
python 2 to 3: https://portingguide.readthedocs.io/en/latest/exceptions.html#the-new-except-syntax

* make relative imports absolute
python 2 to 3: https://portingguide.readthedocs.io/en/latest/imports.html#absolute-imports

* Queue renamed to queue in python 3
Use the six compatibility library to support both python 2 and 3: https://portingguide.readthedocs.io/en/latest/stdlib-reorg.html#renamed-modules

* replace dict.has_key() with in
python 2 to 3: https://portingguide.readthedocs.io/en/latest/dicts.html#removed-dict-has-key

* make dict views compatible with python 3
python 2 to 3: https://portingguide.readthedocs.io/en/latest/dicts.html#dict-views-and-iterators
Where needed, wrapping things that will be a view in python 3 with a list(). For example, if it's accessed with []
Python 3 has no iter*() methods, so just using the values() instead of itervalues() as long as it's not too performance intensive. Note that any minor performance hit of using a list instead of a view will go away when switching to python 3. If it is intensive, we could use the six version.

* Explicitly use truncating division
python 2 to 3: https://portingguide.readthedocs.io/en/latest/numbers.html#division
python 3 treats / as float division. When we want the result to be an integer, use //

* replace map() with list comprehension where a list result is needed.
In python 3, map() returns an iterator.
python 2 to 3: https://portingguide.readthedocs.io/en/latest/iterators.html#new-behavior-of-map-and-filter

* replace filter() with list comprehension
In python 3, filter() returns an interatoooooooooooor.
python 2 to 3: https://portingguide.readthedocs.io/en/latest/iterators.html#new-behavior-of-map-and-filter

* wrap zip() in list() where we need the result to be a list
python 2 to 3: https://portingguide.readthedocs.io/en/latest/iterators.html#new-behavior-of-zip

* clean out some lint
Removes these pylint warnings:
************* Module selfdrive.car.chrysler.chryslercan
W: 15, 0: Unnecessary semicolon (unnecessary-semicolon)
W: 16, 0: Unnecessary semicolon (unnecessary-semicolon)
W: 25, 0: Unnecessary semicolon (unnecessary-semicolon)
************* Module common.dbc
W:101, 0: Anomalous backslash in string: '\?'. String constant might be missing an r prefix. (anomalous-backslash-in-string)
************* Module selfdrive.car.gm.interface
R:102, 6: Redefinition of ret.minEnableSpeed type from float to int (redefined-variable-type)
R:103, 6: Redefinition of ret.mass type from int to float (redefined-variable-type)
************* Module selfdrive.updated
R: 20, 6: Redefinition of r type from int to str (redefined-variable-type)

selfdrive/mapd/default_speeds_generator.py

@@ -205,7 +205,7 @@ class Country(Region):
   def jsonify(self):
     ret_dict = {}
     ret_dict[self.name] = {}
-    for r_name, region in self.regions.iteritems():
+    for r_name, region in self.regions.items():
       ret_dict[self.name].update(region.jsonify())
     ret_dict[self.name]['Default'] = self.rules
     return ret_dict

selfdrive/mapd/mapd.py

@@ -17,7 +17,7 @@ except ImportError as e:
   os.execv(sys.executable, args)
 
 DEFAULT_SPEEDS_BY_REGION_JSON_FILE = BASEDIR + "/selfdrive/mapd/default_speeds_by_region.json"
-import default_speeds_generator
+from selfdrive.mapd import default_speeds_generator
 default_speeds_generator.main(DEFAULT_SPEEDS_BY_REGION_JSON_FILE)
 
 import os
@@ -33,7 +33,7 @@ from common.params import Params
 from common.transformations.coordinates import geodetic2ecef
 from selfdrive.services import service_list
 import selfdrive.messaging as messaging
-from mapd_helpers import MAPS_LOOKAHEAD_DISTANCE, Way, circle_through_points
+from selfdrive.mapd.mapd_helpers import MAPS_LOOKAHEAD_DISTANCE, Way, circle_through_points
 import selfdrive.crash as crash
 from selfdrive.version import version, dirty
 
@@ -176,7 +176,7 @@ def mapsd_thread():
 
         xs = pnts[:, 0]
         ys = pnts[:, 1]
-        road_points = map(float, xs), map(float, ys)
+        road_points = [float(x) for x in xs], [float(y) for y in ys]
 
         if speed < 10:
           curvature_valid = False
@@ -266,8 +266,8 @@ def mapsd_thread():
       if road_points is not None:
         dat.liveMapData.roadX, dat.liveMapData.roadY = road_points
       if curvature is not None:
-        dat.liveMapData.roadCurvatureX = map(float, dists)
-        dat.liveMapData.roadCurvature = map(float, curvature)
+        dat.liveMapData.roadCurvatureX = [float(x) for x in dists]
+        dat.liveMapData.roadCurvature = [float(x) for x in curvature]
 
     dat.liveMapData.mapValid = map_valid
 

selfdrive/mapd/mapd_helpers.py

@@ -91,7 +91,7 @@ def geocode_maxspeed(tags, location_info):
       rule_valid = all(
         tag_name in tags
         and tags[tag_name] == value
-        for tag_name, value in rule['tags'].iteritems()
+        for tag_name, value in rule['tags'].items()
       )
       if rule_valid:
         max_speed = rule['speed']
@@ -102,7 +102,7 @@ def geocode_maxspeed(tags, location_info):
       rule_valid = all(
         tag_name in tags
         and tags[tag_name] == value
-        for tag_name, value in rule['tags'].iteritems()
+        for tag_name, value in rule['tags'].items()
       )
       if rule_valid:
         max_speed = rule['speed']