code: def create_subprocess(self, command):
          
  
          def subprocess_setup():
              # Python installs a SIGPIPE handler by default. This is usually not what
              # non-Python subprocesses expect.
              signal.signal(signal.SIGPIPE, signal.SIG_DFL)
  
          return subprocess.Popen(command,
                                  stdin=self._input_pipe,
                                  stdout=subprocess.PIPE,
                                  preexec_fn=subprocess_setup,
                                  close_fds=True)
docs: http://www.chiark.greenend.org.uk/ucgi/~cjwatson/blosxom/2009-07-02-python-sigpipe.html