fix linter errors

src/pip/_internal/cli/progress_bars.py

@@ -1,10 +1,7 @@
 from __future__ import division
 
-import contextlib
 import itertools
-import logging
 import sys
-import time
 from signal import SIGINT, default_int_handler, signal
 
 from pip._vendor import six
@@ -17,7 +14,7 @@
 from pip._internal.utils.typing import MYPY_CHECK_RUNNING
 
 if MYPY_CHECK_RUNNING:
-    from typing import Any, Iterator, IO
+    from typing import Any
 
 try:
     from pip._vendor import colorama
@@ -26,6 +23,7 @@
 except Exception:
     colorama = None
 
+
 def _select_progress_class(preferred, fallback):
     encoding = getattr(preferred.file, "encoding", None)
 

src/pip/_internal/cli/spinners.py

@@ -16,6 +16,7 @@
 
 logger = logging.getLogger(__name__)
 
+
 class SpinnerInterface(object):
     def spin(self):
         # type: () -> None
@@ -104,6 +105,7 @@ def finish(self, final_status):
         self._update("finished with status '%s'" % (final_status,))
         self._finished = True
 
+
 class RateLimiter(object):
     def __init__(self, min_update_interval_seconds):
         # type: (float) -> None
@@ -120,6 +122,7 @@ def reset(self):
         # type: () -> None
         self._last_update = time.time()
 
+
 @contextlib.contextmanager
 def open_spinner(message):
     # type: (str) -> Iterator[SpinnerInterface]
@@ -144,6 +147,7 @@ def open_spinner(message):
     else:
         spinner.finish("done")
 
+
 @contextlib.contextmanager
 def hidden_cursor(file):
     # type: (IO) -> Iterator[None]
@@ -162,4 +166,3 @@ def hidden_cursor(file):
             yield
         finally:
             file.write(SHOW_CURSOR)
-