python: bulk replace file to open for py3

The builtin function `file` was removed in py3. Use `open` instead.

Signed-off-by: Joe Guo <joeg@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>

python/samba/subunit/run.py

@@ -79,7 +79,7 @@ class TestProtocolClient(unittest.TestResult):
     suite = make_suite()
     # Create a stream (any object with a 'write' method). This should accept
     # bytes not strings: subunit is a byte orientated protocol.
-    stream = file('tests.log', 'wb')
+    stream = open('tests.log', 'wb')
     # Create a subunit result object which will output to the stream
     result = subunit.TestProtocolClient(stream)
     # Optionally, to get timing data for performance analysis, wrap the