graph: use codecs.open. Closes #155138

Makes python3 happier (can't write utf8 data to a file opened without an
encoding)

1 files changed, 3 insertions, 3 deletions

diff --git a/graph.py b/graph.py
index 5cae530..94a71b6 100644
--- a/graph.py
+++ b/graph.py
@@ -28,7 +28,7 @@ import os.path as osp
 import os
 import sys
 import tempfile
-from logilab.common.compat import str_encode
+import codecs
 
 def escape(value):
     """Make <value> usable in a dot file."""
@@ -106,8 +106,8 @@ class DotBackend:
             ppng, outputfile = tempfile.mkstemp(".png", name)
             os.close(pdot)
             os.close(ppng)
-        pdot = open(dot_sourcepath, 'w')
-        pdot.write(str_encode(self.source, 'utf8'))
+        pdot = codecs.open(dot_sourcepath, 'w', encoding='utf8')
+        pdot.write(self.source)
         pdot.close()
         if target != 'dot':
             if sys.platform == 'win32':