Converted CustomForeignKeyField into an importable non-dynamic class

Author: macro1

simple_history/models.py

@@ -147,7 +147,7 @@ def copy_fields(self, model):
                 # Don't allow reverse relations.
                 # ForeignKey knows best what datatype to use for the column
                 # we'll used that as soon as it's finalized by copying rel.to
-                field.__class__ = get_custom_fk_class(type(field))
+                field.__class__ = CustomForeignKeyField
                 field.rel.related_name = '+'
                 field.null = True
                 field.blank = True
@@ -240,7 +240,8 @@ def get_history_user(self, instance):
                 return None
 
 
-class ForeignKeyMixin(object):
+class CustomForeignKeyField(models.ForeignKey):
+
     def get_attname(self):
         return self.name
 
@@ -309,10 +310,6 @@ def contribute_to_class(self, cls, name):
         RelatedField.contribute_to_class(self, cls, name)
 
 
-def get_custom_fk_class(parent_type):
-    return type(str('CustomForeignKey'), (ForeignKeyMixin, parent_type), {})
-
-
 def transform_field(field):
     """Customize field appropriately for use in historical model"""
     field.name = field.attname