Merge master into features

Conflicts:
	src/_pytest/_code/code.py
	src/_pytest/main.py

src/_pytest/cacheprovider.py

@@ -17,6 +17,7 @@ from .pathlib import Path
 from .pathlib import resolve_from_str
 from .pathlib import rm_rf
 from _pytest import nodes
+from _pytest._io import TerminalWriter
 from _pytest.config import Config
 from _pytest.main import Session
 
@@ -418,7 +419,7 @@ def pytest_report_header(config):
 def cacheshow(config, session):
     from pprint import pformat
 
-    tw = py.io.TerminalWriter()
+    tw = TerminalWriter()
     tw.line("cachedir: " + str(config.cache._cachedir))
     if not config.cache._cachedir.is_dir():
         tw.line("cache is empty")