code: def write(self, b):
          
          self._checkClosed()
          self._checkWritable()
          try:
              return self._sock.send(b)
          except error as e:
              # XXX what about EINTR?
              if e.args[0] in _blocking_errnos:
                  return None
              raise
docs: Write the given bytes or bytearray object *b* to the socket
          and return the number of bytes written.  This can be less than
          len(b) if not all data could be written.  If the socket is
          non-blocking and no bytes could be written None is returned.