Add compatibility with older django/python versions

Author: sevdog

rest_framework/filters.py

@@ -96,6 +96,10 @@ def construct_search(self, field_name, queryset):
                     if hasattr(field, "path_infos"):
                         # Update opts to follow the relation.
                         opts = field.path_infos[-1].to_opts
+                    # django < 4.1
+                    elif hasattr(field, 'get_path_info'):
+                        # Update opts to follow the relation.
+                        opts = field.get_path_info()[-1].to_opts
             # Otherwise, use the field with icontains.
             lookup = 'icontains'
         return LOOKUP_SEP.join([field_name, lookup])