bpo-30296 Remove unnecessary tuples, lists, sets, and dicts (#1489)

* Replaced list(<generator expression>) with list comprehension
* Replaced dict(<generator expression>) with dict comprehension
* Replaced set(<list literal>) with set literal
* Replaced builtin func(<list comprehension>) with func(<generator
  expression>) when supported (e.g. any(), all(), tuple(), min(), &
  max())

3 files changed, 3 insertions, 4 deletions

diff --git a/Lib/multiprocessing/context.py b/Lib/multiprocessing/context.py
index a3d491b..c98ee43 100644
--- a/Lib/multiprocessing/context.py
+++ b/Lib/multiprocessing/context.py
@@ -261,7 +261,7 @@ class DefaultContext(BaseContext):
             else:
                 return ['fork', 'spawn']
 
-DefaultContext.__all__ = list(x for x in dir(DefaultContext) if x[0] != '_')
+DefaultContext.__all__ = [x for x in dir(DefaultContext) if x[0] != '_']
 
 #
 # Context types for fixed start method
diff --git a/Lib/multiprocessing/forkserver.py b/Lib/multiprocessing/forkserver.py
index d5ce625..6e09539 100644
--- a/Lib/multiprocessing/forkserver.py
+++ b/Lib/multiprocessing/forkserver.py
@@ -98,8 +98,7 @@ class ForkServer(object):
             if self._preload_modules:
                 desired_keys = {'main_path', 'sys_path'}
                 data = spawn.get_preparation_data('ignore')
-                data = dict((x,y) for (x,y) in data.items()
-                            if x in desired_keys)
+                data = {x: y for x, y in data.items() if x in desired_keys}
             else:
                 data = {}
 
diff --git a/Lib/multiprocessing/sharedctypes.py b/Lib/multiprocessing/sharedctypes.py
index 25cbcf2..7228751 100644
--- a/Lib/multiprocessing/sharedctypes.py
+++ b/Lib/multiprocessing/sharedctypes.py
@@ -115,7 +115,7 @@ def synchronized(obj, lock=None, ctx=None):
             scls = class_cache[cls]
         except KeyError:
             names = [field[0] for field in cls._fields_]
-            d = dict((name, make_property(name)) for name in names)
+            d = {name: make_property(name) for name in names}
             classname = 'Synchronized' + cls.__name__
             scls = class_cache[cls] = type(classname, (SynchronizedBase,), d)
         return scls(obj, lock, ctx)