diff --git a/cimgen/languages/modernpython/lang_pack.py b/cimgen/languages/modernpython/lang_pack.py
index 2f742080..ed10ed9c 100644
--- a/cimgen/languages/modernpython/lang_pack.py
+++ b/cimgen/languages/modernpython/lang_pack.py
@@ -108,7 +108,7 @@ def _primitive_to_data_type(datatype):
 def _set_imports(attributes):
     classes = set()
     for attribute in attributes:
-        if attribute["is_cim_datatype"] or attribute["is_primitive_attribute"]:
+        if attribute["is_datatype_attribute"] or attribute["is_primitive_attribute"]:
             classes.add(attribute["attribute_class"])
 
     result = ""
@@ -146,7 +146,7 @@ def _compute_cim_data_type(attributes) -> dict:
 def _set_cim_data_type(text, render) -> str:
     attribute = eval(render(text))
     cim_data_type = ""
-    if attribute["is_cim_datatype"] or attribute["is_primitive_attribute"]:
+    if attribute["is_datatype_attribute"] or attribute["is_primitive_attribute"]:
         cim_data_type += "\n            "
         cim_data_type += """"cim_data_type": """ + attribute["attribute_class"] + ","
     return cim_data_type
diff --git a/cimgen/languages/modernpython/templates/cimpy_class_template.mustache b/cimgen/languages/modernpython/templates/cimpy_class_template.mustache
index bb91f643..66cc3875 100644
--- a/cimgen/languages/modernpython/templates/cimpy_class_template.mustache
+++ b/cimgen/languages/modernpython/templates/cimpy_class_template.mustache
@@ -36,7 +36,7 @@ class {{class_name}}({{sub_class_of}}):
             "is_enum_attribute": {{#is_enum_attribute}}True{{/is_enum_attribute}}{{^is_enum_attribute}}False{{/is_enum_attribute}},
             "is_list_attribute": {{#is_list_attribute}}True{{/is_list_attribute}}{{^is_list_attribute}}False{{/is_list_attribute}},
             "is_primitive_attribute": {{#is_primitive_attribute}}True{{/is_primitive_attribute}}{{^is_primitive_attribute}}False{{/is_primitive_attribute}},
-            "is_cim_datatype": {{#is_cim_datatype}}True{{/is_cim_datatype}}{{^is_cim_datatype}}False{{/is_cim_datatype}},{{#setCimDataType}}{{.}}{{/setCimDataType}}
+            "is_datatype_attribute": {{#is_datatype_attribute}}True{{/is_datatype_attribute}}{{^is_datatype_attribute}}False{{/is_datatype_attribute}},{{#setCimDataType}}{{.}}{{/setCimDataType}}
         },
     )