diff --git a/tools/run_tests/filter_pull_request_tests.py b/tools/run_tests/filter_pull_request_tests.py
index b7ebe20..981fbe3 100644
--- a/tools/run_tests/filter_pull_request_tests.py
+++ b/tools/run_tests/filter_pull_request_tests.py
@@ -31,7 +31,7 @@
 """Filter out tests based on file differences compared to merge target branch"""
 
 import re
-from subprocess import call, check_output
+from subprocess import check_output
 
 
 class TestSuite:
@@ -105,7 +105,7 @@
   'config\.m4$': [_PHP_TEST_SUITE],
   'CONTRIBUTING\.md$': [],
   'Gemfile$': [_RUBY_TEST_SUITE],
-  'grpc.def$': [_WINDOWS_TEST_SUITE],
+  'grpc\.def$': [_WINDOWS_TEST_SUITE],
   'grpc\.gemspec$': [_RUBY_TEST_SUITE],
   'gRPC\.podspec$': [_OBJC_TEST_SUITE],
   'gRPC\-Core\.podspec$': [_OBJC_TEST_SUITE],
@@ -172,15 +172,11 @@
   :param tests: list of all tests generated by run_tests_matrix.py
   :return: list of relevant tests
   """
-  print("Finding file differences between gRPC %s branch and pull request...\n" % base_branch)
+  print('Finding file differences between gRPC %s branch and pull request...\n' % base_branch)
   changed_files = _get_changed_files(base_branch)
   for changed_file in changed_files:
-    print("  %s" % changed_file)
-  print
-
-  # todo(mattkwong): Remove this
-  # Faking changed files to test test filtering on Jenkins
-  changed_files = ['src/node/something', 'src/python/something']
+    print('  %s' % changed_file)
+  print('')
 
   # Regex that combines all keys in _WHITELIST_DICT
   all_triggers = "(" + ")|(".join(_WHITELIST_DICT.keys()) + ")"
@@ -193,8 +189,8 @@
   for test_suite in _ALL_TEST_SUITES:
     if _can_skip_tests(changed_files, test_suite.triggers):
       for label in test_suite.labels:
-        print("  %s tests safe to skip" % label)
+        print('  %s tests safe to skip' % label)
         skippable_labels.append(label)
-
   tests = _remove_irrelevant_tests(tests, skippable_labels)
   return tests
+