code: def __init__(self, formatter):
      if formatter is None:
          self.formatter = TraceContextTextMapPropagator()
      else:
          self.formatter = formatter
  
file_path: metaflow/metaflow/tracing/propagator.py
imports: import os
  import typing
  from opentelemetry.context import Context
  from opentelemetry.trace.propagation.tracecontext import TraceContextTextMapPropagator
  from opentelemetry.context.context import Context
  from opentelemetry.propagators.textmap import DefaultGetter, DefaultSetter, Getter, Setter, TextMapPropagator, CarrierT
label_desc: Use image node_id 1 to create a new EnvPropagator object from inherited base classes: TextMapPropagator with example: obj = EnvPropagator(formatter)