Add NUTS regions according to config

nomenclature/codelist.py

@@ -726,6 +726,16 @@ def from_directory(
                 except AttributeError:
                     code_list.append(RegionCode(name=c.name, hierarchy="Country"))
 
+        # adding nuts regions
+        if config.definitions.region.nuts:
+            for level, countries in config.definitions.region.nuts.items():
+                for n in nomenclature.nuts.get(
+                    level=int(level[-1]), country_code=countries
+                ):
+                    code_list.append(
+                        RegionCode(name=n.code, hierarchy="NUTS 2021-2024")
+                    )
+
         # importing from an external repository
         for repo in config.definitions.region.repositories:
             repo_path = config.repositories[repo].local_path / "definitions" / "region"

nomenclature/config.py

@@ -41,6 +41,17 @@ def repository_dimension_path(self) -> str:
 
 class RegionCodeListConfig(CodeListConfig):
     country: bool = False
+    nuts: dict[str, list[str]] = None
+
+    @field_validator("nuts")
+    @classmethod
+    def check_nuts(cls, v: dict[str, list[str]] | None) -> dict[str, list[str]] | None:
+        if v and not all(k in ["nuts-1", "nuts-2", "nuts-3"] for k in v.keys()):
+            raise ValueError(
+                "Invalid fields for `nuts` in configuration. "
+                "NUTS level must be 1, 2 and/or 3."
+            )
+        return v
 
 
 class Repository(BaseModel):