docs: def get_headers(hide_env=True):
      """Returns headers dict from request context."""
  
      headers = dict(request.headers.items())
  
      if hide_env and ('show_env' not in request.args):
          for key in ENV_HEADERS:
              try:
                  del headers[key]
              except KeyError:
                  pass
  
      return CaseInsensitiveDict(headers.items())