code: def dump_stream(inbox, handle, delimiter=None):
      
      handle.write(inbox[0])
      delimiter = '\n%s\n' % (delimiter or '')
      handle.write(delimiter)
docs: Writes the first element of the inbox to the provided stream (file handle) 
      delimiting the input by the optional delimiter string. Returns the name of
      the file being written. 
      
      Note that only a single process can have access to a file handle open for 
      writing. Therefore this function should only be used by a non-parallel 
      ``Piper``.
  
      Arguments:
  
        - handle(``file``) File handle open for writing.
        - delimiter(``str``) [default: ``None``] A string which will seperate the
          written items. e.g: ``"END"`` becomes ``"\\nEND\\n"`` in the output 
          stream. The default is an empty string which means that items will be 
          seperated by a blank line i.e.: ``"\\n\\n"`` (two new-line characters).