code: def sendall_stderr(self, s):
          
          while s:
              if self.closed:
                  raise socket.error('Socket is closed')
              sent = self.send_stderr(s)
              s = s[sent:]
          return None
docs: Send data to the channel's "stderr" stream, without allowing partial
          results.  Unlike L{send_stderr}, this method continues to send data
          from the given string until all data has been sent or an error occurs.
          Nothing is returned.
          
          @param s: data to send to the client as "stderr" output.
          @type s: str
          
          @raise socket.timeout: if sending stalled for longer than the timeout
              set by L{settimeout}.
          @raise socket.error: if an error occured before the entire string was
              sent.
              
          @since: 1.1