Renamed instance_property to based_attribute.

Polished the code.
Added old offsets back to the data files.

addons/source-python/data/source-python/entities/csgo/CBasePlayer.ini

@@ -58,8 +58,16 @@ srv_check = False
         offset_windows = 372
 
 
-[instance_property]
+# TODO: Remove when outdated.
+[instance_attribute]
 
+    [[assists]]
+        offset_windows = 4024
+        offset_linux = 4048
+        type = INT
+
+
+[based_attribute]
 
     # from memory import alloc
     # from players.entity import Player

addons/source-python/data/source-python/entities/csgo/CCSPlayer.ini

@@ -57,7 +57,26 @@ srv_check = False
     on_rescue_zone_touch = OnRescueZoneTouch
 
 
-[instance_property]
+# TODO: Remove when outdated.
+[instance_attribute]
+
+    [[mvps]]
+        offset_windows = 12272
+        offset_linux = 12296
+        type = INT
+
+    [[score]]
+        offset_windows = 12312
+        offset_linux = 12336
+        type = INT
+
+    [[clan_tag]]
+        offset_windows = 10240
+        offset_linux = 10264
+        type = STRING_ARRAY
+
+
+[based_attribute]
 
     [[mvps]]
         base = m_bIsHoldingLookAtWeapon

addons/source-python/data/source-python/entities/orangebox/cstrike/CCSPlayer.ini

@@ -50,7 +50,21 @@
     on_rescue_zone_touch = OnRescueZoneTouch
 
 
-[instance_property]
+# TODO: Remove when outdated.
+[instance_attribute]
+
+    [[mvps]]
+        offset_windows = 6384
+        offset_linux = 6404
+        type = INT
+
+    [[clan_tag]]
+        offset_windows = 5628
+        offset_linux = 5648
+        type = STRING_ARRAY
+
+
+[based_attribute]
 
     [[mvps]]
         base = cslocaldata.m_bPlayerDominatingMe.065

addons/source-python/packages/source-python/entities/classes.py

@@ -333,26 +333,38 @@ def _get_server_class(self, class_name, datamap):
                     instance, name, offset, property_contents,
                     _supported_descriptor_types[desc.type])
 
-        # Loop through all instance properties
-        for name, data in manager_contents.get(
-            'instance_property', {}).items():
-
-            # Register the property
-            setattr(instance, name, getattr(
-                self, data.get('method', 'instance_attribute')
-                )(
-                    Key.as_attribute_type(self, data['type']),
-                    instance.properties[
-                        data.get('base_' + PLATFORM, data.get('base'))
-                    ].offset + Key.as_int(
-                        self, data.get(
-                            'offset_' + PLATFORM, data.get('offset', 0)
-                        )
-                    ),
-                    data.get('doc', None)
+        # Loop through all based attributes
+        for name, data in manager_contents.get('based_attribute', {}).items():
+
+            # Resolve the method to register this attribute
+            method = getattr(self, data.get('method', 'instance_attribute'))
+
+            # Resolve the offset of this attribute
+            offset = Key.as_int(
+                self,
+                data.get('offset_' + PLATFORM, data.get('offset', 0))
+            )
+
+            # Resolve the base offset of this attribute
+            base = data.get('base_' + PLATFORM, data.get('base'))
+            try:
+                offset += instance.properties[base].offset
+            except KeyError:
+                raise NameError(
+                    f'"{base}" is not a valid property ' +
+                    f'for attribute "{class_name}.{name}".'
                 )
+
+            # Generate the attribute
+            attribute = method(
+                Key.as_attribute_type(self, data['type']),
+                offset,
+                data.get('doc')
             )
 
+            # Assign the attribute to the instance
+            setattr(instance, name, attribute)
+
         # Get a list of all properties for the current server class
         properties = list(instance.properties)