Fix linting issues.

src/ptvsd/server/options.py

@@ -4,8 +4,6 @@
 
 from __future__ import print_function, with_statement, absolute_import
 
-import os
-
 
 """ptvsd command-line options that need to be globally available.
 """

tests/conftest.py

@@ -213,7 +213,7 @@ def pyfile(request, tmpdir):
         # with, so just replace them with a simple newline.
         line = source[0]
         indent = len(line) - len(line.lstrip())
-        source = [line[indent:] if line.strip() else '\n' for line in source]
+        source = [l[indent:] if l.strip() else '\n' for l in source]
 
         # Write it to file.
         source = ''.join(source)

tests/func/test_break_into_dbg.py

@@ -46,7 +46,7 @@ def test_breakpoint_function(pyfile, run_as, start_method):
         # and attach cases. For attach this is always after wait_for_attach
         from dbgimporter import import_and_enable_debugger
         import_and_enable_debugger()
-        breakpoint()
+        breakpoint() # noqa
         print('break here')
 
     with DebugSession() as session: