code: def __str__(self):
      return EMPTYSTRING.join(
          (EMPTYSTRING.join((fws, part)) for fws, part in self)
      )
  
imports: import re
  import binascii
  import email.quoprimime
  import email.base64mime
  from email.errors import HeaderParseError
  from email import charset
label_desc: Use image node_id 6 for calling the _Accumulator obj's underlying member method code with example usage: obj.__str__() and returns: EMPTYSTRING