Make license-map compatible to both python2 and python3

Change-Id: I0871af54998b9a18aa71fd2d65baeb85a6c52877

tools/bzl/license-map.py

@@ -6,8 +6,8 @@ from __future__ import print_function
 
 import argparse
 from collections import defaultdict
-from shutil import copyfileobj
 from sys import stdout, stderr
+import os
 import xml.etree.ElementTree as ET
 
 
@@ -113,8 +113,8 @@ for n in sorted(graph.keys()):
   print()
   print("[[%s_license]]" % safename)
   print("----")
-  with open(n[2:].replace(":", "/")) as fd:
+  with open(n[2:].replace(":", "/"), "rb") as input:
-    copyfileobj(fd, stdout)
+    os.write(stdout.fileno(), input.read(-1))
   print()
   print("----")
   print()

tools/bzl/license.bzl

@@ -25,7 +25,7 @@ def license_map(name, targets = [], opts = [], **kwargs):
   # post process the XML into our favorite format.
   native.genrule(
     name = "gen_license_txt_" + name,
-    cmd = "python2 $(location //tools/bzl:license-map.py) %s %s > $@" % (" ".join(opts), " ".join(xmls)),
+    cmd = "python $(location //tools/bzl:license-map.py) %s %s > $@" % (" ".join(opts), " ".join(xmls)),
     outs = [ name + ".txt" ],
     tools = tools,
     **kwargs