code: def resolve_prompt_template(prompt_template: Optional[str]) -> str:
      prompt_template = (
          prompt_template
          or """
                  Given these documents, answer the question.
  
                  Documents:
                  {% for doc in documents %}
                      {{ doc.content }}
                  {% endfor %}
  
                  Question: {{question}}
  
                  Answer:
                  """
      )
      return prompt_template
  
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 5 for calling a global function with example usage: resolve_prompt_template(prompt_template) and returns: prompt_template