Fix NameError in unit tests

* at the same time as making mypy shut up

src/neo4j_graphrag/llm/anthropic_llm.py

@@ -13,7 +13,7 @@
 #  limitations under the License.
 from __future__ import annotations
 
-from typing import Any, Iterable, Optional, TYPE_CHECKING, cast
+from typing import Any, Iterable, Optional, TYPE_CHECKING
 
 from pydantic import ValidationError
 
@@ -81,7 +81,7 @@ def get_messages(
                 raise LLMGenerationError(e.errors()) from e
             messages.extend(message_history)
         messages.append(UserMessage(content=input).model_dump())
-        return cast(Iterable[MessageParam], messages)
+        return messages  # type: ignore
 
     def invoke(
         self,

src/neo4j_graphrag/llm/cohere_llm.py

@@ -14,7 +14,7 @@
 #  limitations under the License.
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Any, Optional, cast
+from typing import TYPE_CHECKING, Any, Optional
 from pydantic import ValidationError
 
 from neo4j_graphrag.exceptions import LLMGenerationError
@@ -94,7 +94,7 @@ def get_messages(
                 raise LLMGenerationError(e.errors()) from e
             messages.extend(message_history)
         messages.append(UserMessage(content=input).model_dump())
-        return cast(ChatMessages, messages)
+        return messages  # type: ignore
 
     def invoke(
         self,

src/neo4j_graphrag/llm/ollama_llm.py

@@ -13,7 +13,7 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 from __future__ import annotations
-from typing import Any, Optional, Sequence, TYPE_CHECKING, cast
+from typing import Any, Optional, Sequence, TYPE_CHECKING
 
 from pydantic import ValidationError
 
@@ -71,7 +71,7 @@ def get_messages(
                 raise LLMGenerationError(e.errors()) from e
             messages.extend(message_history)
         messages.append(UserMessage(content=input).model_dump())
-        return cast(Sequence[Message], messages)
+        return messages  # type: ignore
 
     def invoke(
         self,

src/neo4j_graphrag/llm/openai_llm.py

@@ -15,7 +15,7 @@
 from __future__ import annotations
 
 import abc
-from typing import TYPE_CHECKING, Any, Iterable, Optional, cast
+from typing import TYPE_CHECKING, Any, Iterable, Optional
 
 from pydantic import ValidationError
 
@@ -81,7 +81,7 @@ def get_messages(
                 raise LLMGenerationError(e.errors()) from e
             messages.extend(message_history)
         messages.append(UserMessage(content=input).model_dump())
-        return cast(Iterable[ChatCompletionMessageParam], messages)
+        return messages  # type: ignore
 
     def invoke(
         self,