code: def spawn(self, process):
      
      self._assert_started()
      process.bind(self)
      self.http.mount_process(process)
      self._processes[process.pid] = process
      process.initialize()
      return process.pid
docs: Spawn a process.
  
      Spawning a process binds it to this context and assigns the process a
      pid which is returned.  The process' ``initialize`` method is called.
  
      Note: A process cannot send messages until it is bound to a context.
  
      :param process: The process to bind to this context.
      :type process: :class:`Process`
      :return: The pid of the process.
      :rtype: :class:`PID`