Dont put biplist in backports

src/calibre/utils/open_with/osx.py

@@ -9,9 +9,14 @@
 from collections import defaultdict
 
 from calibre.ptempfile import TemporaryDirectory
+from calibre.constants import ispy3
 from calibre.utils.icu import numeric_sort_key
 from polyglot.builtins import iteritems, string_or_bytes
-from polyglot.plistlib import loads_binary_or_xml as loads
+
+if ispy3:
+    from plistlib import loads
+else:
+    from biplist import readPlistFromString as loads
 
 application_locations = ('/Applications', '~/Applications', '~/Desktop')
 

src/polyglot/plistlib.py

@@ -8,7 +8,5 @@
 
 if is_py3:
     from plistlib import loads, dumps, Data  # noqa
-    loads_binary_or_xml = loads
 else:
     from plistlib import readPlistFromString as loads, writePlistToString as dumps, Data  # noqa
-    from backports.biplist import readPlistFromString as loads_binary_or_xml  # noqa