use TemplateColumn instead of own class

netbox/dcim/tables/__init__.py

@@ -1,5 +1,4 @@
 from .cables import *
-from .columns import *
 from .connections import *
 from .devices import *
 from .devicetypes import *

netbox/dcim/tables/columns.py

@@ -1,21 +0,0 @@
-import django_tables2 as tables
-
-__all__ = (
-    'SpeedColumn',
-)
-
-
-class SpeedColumn(tables.TemplateColumn):
-    """
-    Humanize the speed in the column view
-    """
-    template_code = """
-        {% load helpers %}
-        {{ value|humanize_speed|placeholder }}
-        """
-
-    def __init__(self, *args, **kwargs):
-        super().__init__(template_code=self.template_code, *args, **kwargs)
-
-    def value(self, value, **kwargs):
-        return super().value(value=value, **kwargs) if value else None

netbox/dcim/tables/devices.py

@@ -5,7 +5,6 @@ from tenancy.tables import ContactsColumnMixin, TenancyColumnsMixin
 
 from netbox.tables import NetBoxTable, columns
 
-from .columns import *
 from .template_code import *
 
 __all__ = (
@@ -546,7 +545,8 @@ class InterfaceTable(ModularDeviceComponentTable, BaseInterfaceTable, PathEndpoi
         }
     )
     mgmt_only = columns.BooleanColumn()
-    speed_formatted = SpeedColumn(
+    speed_formatted = columns.TemplateColumn(
+        template_code='{% load helpers %}{{ value|humanize_speed }}',
         accessor=Accessor('speed'),
         verbose_name='Speed'
     )