Remove unused or redundant imports in concurrent.futures and multiprocessing.

Lib/concurrent/futures/_base.py

@@ -4,7 +4,6 @@
 __author__ = 'Brian Quinlan (brian@sweetapp.com)'
 
 import collections
-import functools
 import logging
 import threading
 import time

Lib/concurrent/futures/process.py

@@ -221,7 +221,7 @@ def shutdown_worker():
         assert sentinels
         try:
             result_item = result_queue.get(sentinels=sentinels)
-        except SentinelReady as e:
+        except SentinelReady:
             # Mark the process pool broken so that submits fail right now.
             executor = executor_reference()
             if executor is not None:
@@ -291,7 +291,6 @@ def _check_system_limits():
             raise NotImplementedError(_system_limited)
     _system_limits_checked = True
     try:
-        import os
         nsems_max = os.sysconf("SC_SEM_NSEMS_MAX")
     except (AttributeError, ValueError):
         # sysconf not available or setting not available

Lib/concurrent/futures/thread.py

@@ -74,7 +74,7 @@ def _worker(executor_reference, work_queue):
                 work_queue.put(None)
                 return
             del executor
-    except BaseException as e:
+    except BaseException:
         _base.LOGGER.critical('Exception in worker', exc_info=True)
 
 class ThreadPoolExecutor(_base.Executor):

Lib/multiprocessing/dummy/__init__.py

@@ -46,9 +46,7 @@
 import sys
 import weakref
 import array
-import itertools
 
-from multiprocessing import TimeoutError, cpu_count
 from multiprocessing.dummy.connection import Pipe
 from threading import Lock, RLock, Semaphore, BoundedSemaphore
 from threading import Event, Condition

Lib/multiprocessing/forking.py

@@ -35,7 +35,6 @@
 import os
 import sys
 import signal
-import select
 
 from multiprocessing import util, process
 
@@ -101,7 +100,6 @@ def _rebuild_partial(func, args, keywords):
 #
 
 if sys.platform != 'win32':
-    import time
     import select
 
     exit = os._exit
@@ -170,7 +168,7 @@ def terminate(self):
             if self.returncode is None:
                 try:
                     os.kill(self.pid, signal.SIGTERM)
-                except OSError as e:
+                except OSError:
                     if self.wait(timeout=0.1) is None:
                         raise
 
@@ -186,11 +184,9 @@ def thread_is_spawning():
     import _thread
     import msvcrt
     import _subprocess
-    import time
 
-    from pickle import dump, load, HIGHEST_PROTOCOL
+    from pickle import load, HIGHEST_PROTOCOL
     from _multiprocessing import win32
-    from .util import Finalize
 
     def dump(obj, file, protocol=None):
         ForkingPickler(file, protocol).dump(obj)

Lib/multiprocessing/heap.py

@@ -34,7 +34,6 @@
 
 import bisect
 import mmap
-import tempfile
 import os
 import sys
 import threading

Lib/multiprocessing/managers.py

@@ -39,19 +39,15 @@
 # Imports
 #
 
-import os
 import sys
-import weakref
 import threading
 import array
 import queue
 
 from traceback import format_exc
-from pickle import PicklingError
 from multiprocessing import Process, current_process, active_children, Pool, util, connection
 from multiprocessing.process import AuthenticationString
-from multiprocessing.forking import exit, Popen, assert_spawning, ForkingPickler
+from multiprocessing.forking import exit, Popen, ForkingPickler
-from multiprocessing.util import Finalize, info
 
 #
 # Register some things for pickling

Lib/multiprocessing/queues.py

@@ -39,7 +39,6 @@
 import threading
 import collections
 import time
-import atexit
 import weakref
 import errno
 

Lib/multiprocessing/reduction.py

@@ -41,7 +41,6 @@
 import threading
 import struct
 
-import _multiprocessing
 from multiprocessing import current_process
 from multiprocessing.forking import Popen, duplicate, close, ForkingPickler
 from multiprocessing.util import register_after_fork, debug, sub_debug
@@ -61,7 +60,6 @@
 #
 
 if sys.platform == 'win32':
-    import _subprocess
     from _multiprocessing import win32
 
     def send_handle(conn, handle, destination_pid):

Lib/multiprocessing/sharedctypes.py

@@ -32,7 +32,6 @@
 # SUCH DAMAGE.
 #
 
-import sys
 import ctypes
 import weakref
 

Lib/multiprocessing/synchronize.py

@@ -37,14 +37,11 @@
     ]
 
 import threading
-import os
 import sys
 
-from time import time as _time, sleep as _sleep
-
 import _multiprocessing
 from multiprocessing.process import current_process
-from multiprocessing.util import Finalize, register_after_fork, debug
+from multiprocessing.util import register_after_fork, debug
 from multiprocessing.forking import assert_spawning, Popen
 
 # Try to import the mp.synchronize module cleanly, if it fails

Lib/multiprocessing/util.py

@@ -36,7 +36,6 @@
 import itertools
 import weakref
 import atexit
-import select
 import threading        # we want threading to install it's
                         # cleanup function before multiprocessing does
 
@@ -86,7 +85,7 @@ def get_logger():
     Returns logger used by multiprocessing
     '''
     global _logger
-    import logging, atexit
+    import logging
 
     logging._acquireLock()
     try: