parameters: (self, original, updated, channel_id, output)
docstring: Takes two marshaled common.Config messages and computes the config update which
          transitions between the two.
  
          params:
              original: The original config message.
              updated: The updated config message.
              channel_id: The name of the channel for this update.
              output: A file to write the JSON document to.
docstring_summary: Takes two marshaled common.Config messages and computes the config update which
          transitions between the two.
docstring_tokens: Takes two marshaled common . Config messages and computes the config update which transitions between the two .
function: def compute_update(self, original, updated, channel_id, output):
          """
          Takes two marshaled common.Config messages and computes the config update which
          transitions between the two.
  
          params:
              original: The original config message.
              updated: The updated config message.
              channel_id: The name of the channel for this update.
              output: A file to write the JSON document to.
          """
          try:
              call([self.configtxlator,
                    "--original", original,
                    "--updated", updated,
                    "--channel_id", channel_id,
                    "--output", "{}/{}".format(self.filepath, output)
                    ])
          except Exception as e:
              err_msg = "configtxlator compute update fail! "
              raise Exception(err_msg + str(e))
function_tokens: def compute_update ( self , original , updated , channel_id , output ) : try : call ( [ self . configtxlator , "--original" , original , "--updated" , updated , "--channel_id" , channel_id , "--output" , "{}/{}" . format ( self . filepath , output ) ] ) except Exception as e : err_msg = "configtxlator compute update fail! " raise Exception ( err_msg + str ( e ) )