old_contents: #!/usr/bin/env python
  
  from __future__ import print_function
  from base_slave import BaseSlave
  
  class URLSlave(BaseSlave):
      def __init__(self, config, UploaderClass):
          super(URLSlave, self).__init__(config)
          self.uploader_class = UploaderClass(config)
  
      # implementation abstract method
      def do_job(self, job):
          """
          type job: (index, fileid, source)
          rtype: (index, new fileid, status, log)
          
          do not throw any exception
          """
          serial = job[0]
          fileid = job[1]
          src = job[2]
          
          # TODO: read source
  
          (new_fileid, status, log) = self.uploader_class.upload((fileid, src))
  
          return (serial, new_fileid, status, log)
  
  
new_contents: #!/usr/bin/env python
  
  from __future__ import print_function
  from base_slave import BaseSlave
  
  class URLSlave(BaseSlave):
      def __init__(self, config, UploaderClass):
          super(URLSlave, self).__init__(config)
          self.uploader_class = UploaderClass(config)
  
      # implementation of abstract method
      def do_job(self, job):
          """
          type job: (index, fileid, source)
          rtype: (index, new fileid, status, log)
          
          do not throw any exception
          """
          serial = job[0]
          fileid = job[1]
          src = job[2]
          
          # TODO: read source
  
          (new_fileid, status, log) = self.uploader_class.upload((fileid, src))
  
          return (serial, new_fileid, status, log)
  
  
subject: fix typo