datafile: acess datasets with byte keys rather than string

Required by new h5py API

1 files changed, 4 insertions, 2 deletions

diff --git a/datafile.py b/datafile.py
index 5b83bf0..5a09c4d 100644
--- a/datafile.py
+++ b/datafile.py
@@ -116,9 +116,11 @@ class _DataSet(object):
         return '<%s>@<%s>' % (self.name, self._df.path)
 
     def _slice_single_component(self, it, rl, component = None):
-        querystr = '%s it=%d tl=0 rl=%d' % (self.name, it, rl)
+        querystr = b'%s it=%d tl=0 rl=%d' % (self.name.encode('ascii'), it, rl)
+
         if component is not None:
-            querystr += ' c=%d' % component
+            querystr += b' c=%d' % component
+
         data   = self._df._f[querystr]
         layout = _SliceLayout(data.attrs['origin'], data.attrs['delta'], data.shape[::-1])
         return _DataSlice(data, layout)