diff --git a/modernpython/primitive_header.py b/modernpython/primitive_header.py
index 8fa95acc..c8e79e7d 100644
--- a/modernpython/primitive_header.py
+++ b/modernpython/primitive_header.py
@@ -3,4 +3,4 @@
 from ..utils.profile import Profile
 from .enum import *
 
-String = Primitive("String",str, [Profile.EQBD, Profile.OP, Profile.SSH, Profile.EQ, Profile.DY, Profile.DL, Profile.SV, Profile.SC, ])
\ No newline at end of file
+String = Primitive(name="String",type=str, profiles=[Profile.EQBD, Profile.OP, Profile.SSH, Profile.EQ, Profile.DY, Profile.DL, Profile.SV, Profile.SC, ])
\ No newline at end of file
diff --git a/modernpython/templates/cimdatatype_template.mustache b/modernpython/templates/cimdatatype_template.mustache
index 6ca8c7e1..d2d553fe 100644
--- a/modernpython/templates/cimdatatype_template.mustache
+++ b/modernpython/templates/cimdatatype_template.mustache
@@ -3,7 +3,7 @@
 Generated from the CGMES 3 files via cimgen: https://github.com/sogno-platform/cimgen
 """
 
-{{class_name}} = CIMDatatype("{{class_name}}", {{data_type}}, {{unit}}, {{multiplier}}, [{{#class_origin}}Profile.{{origin}},{{/class_origin}}])
+{{class_name}} = CIMDatatype(name="{{class_name}}", type={{data_type}}, symbol={{unit}}, multiplier={{multiplier}}, profiles=[{{#class_origin}}Profile.{{origin}},{{/class_origin}}])
 
 """
 {{{wrapped_class_comment}}}
diff --git a/modernpython/templates/primitive_template.mustache b/modernpython/templates/primitive_template.mustache
index 40a1e040..91282052 100644
--- a/modernpython/templates/primitive_template.mustache
+++ b/modernpython/templates/primitive_template.mustache
@@ -3,7 +3,7 @@
 Generated from the CGMES 3 files via cimgen: https://github.com/sogno-platform/cimgen
 """
 
-{{class_name}} = Primitive("{{class_name}}", {{data_type}}, [{{#class_origin}}Profile.{{origin}}, {{/class_origin}}])
+{{class_name}} = Primitive(name="{{class_name}}", type={{data_type}}, profiles=[{{#class_origin}}Profile.{{origin}}, {{/class_origin}}])
 
 """
 {{{wrapped_class_comment}}}
diff --git a/modernpython/utils/datatypes.py b/modernpython/utils/datatypes.py
index b6709344..b14b2ee2 100644
--- a/modernpython/utils/datatypes.py
+++ b/modernpython/utils/datatypes.py
@@ -1,7 +1,5 @@
-import importlib
-from dataclasses import Field, fields
-from functools import cached_property
-from typing import Any, TypeAlias, TypedDict
+from pydantic import Field
+from typing import List
 
 from .constants import NAMESPACES
 from pydantic.dataclasses import dataclass
@@ -13,39 +11,13 @@
 @dataclass(config=DataclassConfig)
 class Primitive:
 
-    def __init__(self, name: str, type, profiles: set[BaseProfile]):
-      self.name = name
-      self.type = type
-      self.profiles = profiles
-
-    def get_name(self) -> str:
-        return self.name
-    
-    def get_type(self):
-        return self.type
-
-    @cached_property
-    def namespace(self) -> str:
-        """Returns the namespace. By default, the namespace is the cim namespace for all resources.
-        Custom resources can override this.
-        """
-        return NAMESPACES["cim"]
-    
-    @cached_property
-    def get_profiles(self) -> set[BaseProfile]:
-        return self.profiles
+    name: str = Field(frozen=True)
+    type: object = Field(frozen=True)
+    namespace: str = Field(frozen=True, default=NAMESPACES["cim"])
+    profiles: List[BaseProfile] = Field(frozen=True)
 
 @dataclass(config=DataclassConfig)
 class CIMDatatype(Primitive):
-     
-    def __init__(self,
-                name: str, type, symbol: UnitSymbol, multiplier: UnitMultiplier, profiles: set[BaseProfile]):
-        super().__init__(name, type, profiles)
-        self.multiplier = multiplier
-        self.symbol = symbol
-    
-    def get_multiplier(self) -> UnitMultiplier:
-        return self.multiplier
-        
-    def get_symbol(self) -> UnitSymbol:
-        return self.symbol
\ No newline at end of file
+
+    multiplier: UnitMultiplier = Field(frozen=True)
+    symbol: UnitSymbol = Field(frozen=True)