code: def _initialize_workflow(self):
          
  
          try:
  
              self._prof.prof('initializing workflow', uid=self._uid)
  
              for p in self._workflow:
                  p._assign_uid(self._sid)
  
              self._prof.prof('workflow initialized', uid=self._uid)
  
          except Exception, ex:
              self._logger.exception(
                  'Fatal error while initializing workflow: %s' % ex)
              raise
docs: **Purpose**: Initialize the PST of the workflow with a uid and type checks