class_docstr: Resolves the OpenAIGenerator.
code: def resolve(self, model_key: str, api_key: str) -> Any:
      # does the model_key match the pattern OpenAI GPT pattern?
      if re.match(r"^gpt-4-.*", model_key) or re.match(
          r"^gpt-3.5-.*", model_key
      ):
          return OpenAIGenerator(model=model_key, api_key=api_key)
      return None
  
imports: import re
  from abc import ABC, abstractmethod
  from typing import Optional, Any
  from huggingface_hub import HfApi
  from haystack import Pipeline
  from haystack.components.builders.answer_builder import AnswerBuilder
  from haystack.components.builders.prompt_builder import PromptBuilder
  from haystack.components.embedders import SentenceTransformersTextEmbedder
  from haystack.components.generators import OpenAIGenerator, HuggingFaceTGIGenerator
  from haystack.components.retrievers.in_memory import InMemoryEmbeddingRetriever
  from haystack.dataclasses import Answer
  from haystack.document_stores.types import DocumentStore
  from haystack.document_stores.in_memory import InMemoryDocumentStore
label_desc: Use image node_id 1 for calling the _OpenAIResolved obj's underlying member method code with example usage: obj.resolve(model_key, api_key) and returns: None, OpenAIGenerator