ds_store now takes advantage of Pythons ability to decode binary plists (since 3.4), so we can drop its biplist dependency.
The call to biplist.Data() in custom_dsstore.py doesn't seem to do anything, and from what I can tell can just be removed. i.e:
diff --git a/contrib/macdeploy/custom_dsstore.py b/contrib/macdeploy/custom_dsstore.py
index dc1c1882d..e475bc6c3 100755
--- a/contrib/macdeploy/custom_dsstore.py
+++ b/contrib/macdeploy/custom_dsstore.py
@@ -47,6 +47,7 @@ alias.volume.disk_image_alias.target.filename = package_name_ns + '.temp.dmg'
alias.volume.disk_image_alias.target.carbon_path = 'Macintosh HD:Users:\x00bitcoinuser:\x00Documents:\x00bitcoin:\x00bitcoin:\x00' + package_name_ns + '.temp.dmg'
alias.volume.disk_image_alias.target.posix_path = 'Users/bitcoinuser/Documents/bitcoin/bitcoin/' + package_name_ns + '.temp.dmg'
alias.target.carbon_path = package_name_ns + ':.background:\x00background.tiff'
+assert(biplist.Data(alias.to_bytes()) == alias.to_bytes())
icvp['backgroundImageAlias'] = biplist.Data(alias.to_bytes())
ds['.']['icvp'] = icvp