code: def rfc822_unescape(content: str) -> str:
      """Reverse RFC-822 escaping by removing leading whitespaces from content."""
      lines = content.splitlines()
      if len(lines) == 1:
          return lines[0].lstrip()
      return "\n".join(
          (lines[0].lstrip(), textwrap.dedent("\n".join(lines[1:])))
      )
  
imports: import os
  import stat
  import textwrap
  from email import message_from_file
  from email.message import Message
  from tempfile import NamedTemporaryFile
  from typing import Optional, List
  from distutils.util import rfc822_escape
  from .None import _normalization, _reqs
  from .extern.packaging.markers import Marker
  from .extern.packaging.requirements import Requirement
  from .extern.packaging.version import Version
  from .warnings import SetuptoolsDeprecationWarning
label_desc: Use image node_id 2 for calling a global function with example usage: rfc822_unescape(content) and returns: str, lines