code: def __init__(
      self,
      _subtype="mixed",
      boundary=None,
      _subparts=None,
      *,
      policy=None,
      **_params,
  ):
      """Creates a multipart/* type message.
  
      By default, creates a multipart/mixed message, with proper
      Content-Type and MIME-Version headers.
  
      _subtype is the subtype of the multipart content type, defaulting to
      `mixed'.
  
      boundary is the multipart boundary string.  By default it is
      calculated as needed.
  
      _subparts is a sequence of initial subparts for the payload.  It
      must be an iterable object, such as a list.  You can always
      attach new subparts to the message by using the attach() method.
  
      Additional parameters for the Content-Type header are taken from the
      keyword arguments (or passed into the _params argument).
      """
      MIMEBase.__init__(
          self, "multipart", _subtype, policy=policy, **_params
      )
  
      # Initialise _payload to an empty list as the Message superclass's
      # implementation of is_multipart assumes that _payload is a list for
      # multipart messages.
      self._payload = []
  
      if _subparts:
          for p in _subparts:
              self.attach(p)
      if boundary:
          self.set_boundary(boundary)
  
label_desc: Use image node_id 1 to create a new MIMEMultipart object from inherited base classes: MIMEBase with example: obj = MIMEMultipart(_subtype, boundary, _subparts)