code: def init_tracing():
      global tracer_provider
      if tracer_provider is not None:
          print("Tracing already initialized", file=sys.stderr)
          return
  
      from .propagator import EnvPropagator
  
      set_global_textmap(EnvPropagator(None))
      span_exporter = get_span_exporter()
  
      if "METAFLOW_KUBERNETES_POD_NAMESPACE" in os.environ:
          service_name = "metaflow-kubernetes"
      elif "AWS_BATCH_JOB_ID" in os.environ:
          service_name = "metaflow-awsbatch"
      else:
          service_name = "metaflow-local"
  
      tracer_provider = TracerProvider(
          resource=Resource.create({SERVICE_NAME: service_name})
      )
      trace_api.set_tracer_provider(tracer_provider)
  
      span_processor = BatchSpanProcessor(span_exporter)
      tracer_provider.add_span_processor(span_processor)
  
      from opentelemetry.instrumentation.requests import (
          RequestsInstrumentor,
      )
  
      RequestsInstrumentor().instrument()
  
imports: import os
  import sys
  from opentelemetry.sdk.trace import TracerProvider
  from opentelemetry.sdk.trace.export import BatchSpanProcessor
  from opentelemetry.propagate import set_global_textmap
  from opentelemetry.sdk.resources import SERVICE_NAME, Resource
  from opentelemetry.trace.span import format_trace_id
  from opentelemetry.propagate import extract, inject
  from functools import wraps
  import contextlib
  from typing import Dict, List, Optional
  from opentelemetry import trace, context
  from .span_exporter import get_span_exporter
label_desc: Use image node_id 1 for calling a global function with example usage: init_tracing() without return types