just delete the duplicated models, not the useful ones

base_partner_merge/__init__.py

@@ -1,5 +1,4 @@
 # -*- coding: utf-8 -*-
 
-from . import base_partner_merge  # NOQA
-from .hooks import post_load_hook
 from . import models
+from .hooks import post_load_hook

base_partner_merge/hooks.py

@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 # © 2017 Therp BV <http://therp.nl>
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+import sys
 import inspect
 from openerp.models import MetaModel
 
@@ -16,15 +17,20 @@ def post_load_hook():
         if 'graph' in frame.f_locals:
             graph = frame.f_locals['graph']
             package = frame.f_locals['package']
-            package.data['data'].remove('views/base_partner_merge.xml')
             if any(p.name == 'crm' for p in graph):
                 # so crm is installed, then we need to remove your model
                 # from the list of models to be registered
                 # TODO: this could be smarter and only ditch models that need
                 # to be ditched (if crm is in their mro)
-                MetaModel.module_to_models['base_partner_merge'] = []
-                # and in this case, we also don't want to load our xml files
-            else:
-                # if crm is not installed, we
+                our_version = 'openerp.addons.base_partner_merge.' \
+                    'models.base_partner_merge'
+                classes_to_ditch = [_class for _name, _class in
+                    inspect.getmembers(sys.modules[our_version],
+                    lambda member: inspect.isclass(member)
+                    and member.__module__ == our_version)]
+                for _class in classes_to_ditch:
+                    MetaModel.module_to_models['base_partner_merge'] \
+                        .remove(_class)
+                # and in this case, we also don't want to load our xml file
                 package.data['data'].remove('views/base_partner_merge.xml')
             break

base_partner_merge/models/__init__.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
 
+from . import base_partner_merge  # noqa
 from . import res_partner
 from . import base_partner_merge_automatic_wizard