Avoid copybara import error

src/proto/gen_build_yaml.py

@@ -15,6 +15,7 @@
 
 
 """Generates the appropriate build.json data for all the proto files."""
+from __future__ import print_function
 import yaml
 import collections
 import os
@@ -36,6 +37,10 @@ def update_deps(key, proto_filename, deps, deps_external, is_trans, visited):
             deps_external[key] = []
           deps_external[key].append(imp_proto[:-6])
           continue
+        # In case that the path is changed by copybara,
+        # revert the change to avoid file error.
+        if imp_proto.startswith('third_party/grpc'):
+          imp_proto = imp_proto[17:]          
         if key not in deps: deps[key] = []
         deps[key].append(imp_proto[:-6])
         if is_trans:
@@ -66,7 +71,7 @@ def main():
     'proto_transitive_external_deps': deps_external_trans
   }
 
-  print yaml.dump(json)
+  print(yaml.dump(json))
 
 if __name__ == '__main__':
   main()