diff --git a/src/django_bim/fields/model/actor/field_model_ifc_actor_select.py b/src/django_bim/fields/model/actor/field_model_ifc_actor_select.py
index c32fdb3..ef9525e 100644
--- a/src/django_bim/fields/model/actor/field_model_ifc_actor_select.py
+++ b/src/django_bim/fields/model/actor/field_model_ifc_actor_select.py
@@ -1,33 +1,107 @@
+# -*- coding: utf-8 -*-
+
+
+# =============================================================================
+# Docstring
+# =============================================================================
+
+"""
+
+===================================
+
 https://ifc43-docs.standards.buildingsmart.org/IFC/RELEASE/IFC4x3/HTML/lexical/IfcActorSelect.htm
 
+
+"""
+
+
+# =============================================================================
+# Import
+# =============================================================================
+
+# Import | Standard Library
+from typing import Literal
+
+# Import | Libraries
 from django.contrib.contenttypes.fields import GenericForeignKey
 from django.contrib.contenttypes.models import ContentType
 from django.db import models
 from django.utils.translation import gettext_lazy as _
 
+# Import | Local Modules
+
+
+# =============================================================================
+# Classes
+# =============================================================================
+
+
 class IfcActorSelectField(models.Field):
-    description = _(
-        "A field that can refer to an IfcOrganization, IfcPerson, or IfcPersonAndOrganization"
+    """
+    ...
+    """
+
+    description: str = _(
+        message="A field that can refer to an IfcOrganization, IfcPerson, or IfcPersonAndOrganization"
     )
 
-    def __init__(self, *args, **kwargs):
+    def __init__(self, *args, **kwargs) -> None:
+        """
+        ...
+        """
         super().__init__(*args, **kwargs)
-        self.object_id_field = 'object_id'
-        self.content_type_field = 'content_type'
+        self.object_id_field = "object_id"
+        self.content_type_field = "content_type"
 
-    def contribute_to_class(self, cls, name, private_only=False, **kwargs):
+    def contribute_to_class(
+        self,
+        cls,
+        name,
+        private_only=False,
+        **kwarg,
+    ) -> None:
+        """
+        ...
+        """
         self.name = name
         self.model = cls
-        ct_field = models.ForeignKey(ContentType, on_delete=models.CASCADE, limit_choices_to={
-            'model__in': ('ifcperson', 'ifcorganization', 'ifcpersonandorganization')
-        })
+        ct_field = models.ForeignKey(
+            ContentType,
+            on_delete=models.CASCADE,
+            limit_choices_to={
+                "model__in": (
+                    "ifcperson",
+                    "ifcorganization",
+                    "ifcpersonandorganization",
+                ),
+            },
+        )
         fk_field = models.PositiveIntegerField()
         cls.add_to_class(self.content_type_field, ct_field)
         cls.add_to_class(self.object_id_field, fk_field)
-        actor = GenericForeignKey(self.content_type_field, self.object_id_field)
+        actor = GenericForeignKey(
+            ct_field=self.content_type_field, fk_field=self.object_id_field
+        )
         cls.add_to_class(name, actor)
 
-        super().contribute_to_class(cls, name, private_only, **kwargs)
+        super().contribute_to_class(
+            cls=cls,
+            name=name,
+            private_only=private_only,
+            **kwargs,
+        )
+
+    def get_internal_type(self) -> Literal["IfcActorSelectField"]:
+        """
+        ...
+        """
+        return "IfcActorSelectField"
+
+
+# =============================================================================
+# Export
+# =============================================================================
 
-    def get_internal_type(self):
-        return 'IfcActorSelectField'
+__all__: list[str] = [
+    "IfcActorSelectField",
+]