Fixed style issues reported by flake8. Added gc.collect.

The latter is in the hope of it fixing the test under PyPy.

Author: torokati44

tests/test_consume.py

@@ -1,3 +1,6 @@
+import gc
+
+
 def test_consume_argument(capture):
     from pybind11_tests import Box, Filter
 
@@ -15,24 +18,25 @@ def test_consume_argument(capture):
     assert Box.get_num_boxes() == 2
 
     with capture:
-        filt.process(box_1) # box_1 is not big enough, but process() leaks it
+        filt.process(box_1)  # box_1 is not big enough, but process() leaks it
     assert capture == "Box is processed by Filter."
 
     assert Box.get_num_boxes() == 2
 
     with capture:
-        filt.process(box_8) # box_8 is destroyed by process() of filt
+        filt.process(box_8)  # box_8 is destroyed by process() of filt
     assert capture == """
         Box is processed by Filter.
         Box destroyed.
     """
 
-    assert Box.get_num_boxes() == 1 # box_1 still exists somehow, but we can't access it
+    assert Box.get_num_boxes() == 1  # box_1 still exists somehow, but we can't access it
 
     with capture:
         del filt
         del box_1
         del box_8
+        gc.collect()
     assert capture == "Filter destroyed."
 
-    assert Box.get_num_boxes() == 1 # 1 box is leaked, and we can't do anything
+    assert Box.get_num_boxes() == 1  # 1 box is leaked, and we can't do anything