code: def add_header(self, name, value):
          '''Attach an email header to send with the message.
  
          :param name: The name of the header value.
          :param value: The header value.
          '''
          if self.headers is None:
              self.headers = []
          self.headers.append(dict(Name=name, Value=value)f add_header(self, name, value):
          '''Attach an email header to send with the message.
  
          :param name: The name of the header value.
          :param value: The header value.
          '''
          if self.headers is None:
              self.headers = []
          self.headers.append(dict(Name=name, Value=value))
docs: Attach an email header to send with the message.
  
          :param name: The name of the header value.
          :param value: The header value.