docs: def driveFunction(self):
          """
          Drive the function/subfunction call.
  
          Input:
             Self with request filled in.
  
          Output:
             Request Handle updated with the results.
             Overall return code - 0: successful, non-zero: error
          """
  
          if self.function == 'HELP':
              # General help for all functions.
              self.printLn("N", "")
              self.printLn("N", "Usage:")
              self.printLn("N", "  python " + self.cmdName + " --help")
              for key in sorted(ReqHandle.funcHandler):
                  ReqHandle.funcHandler[key][0](self)
              self.printLn("N", "")
              self.printLn("N", "Operand(s):")
              for key in sorted(ReqHandle.funcHandler):
                  ReqHandle.funcHandler[key][1](self)
              self.printLn("N", "")
              self.updateResults({}, reset=1)
          elif self.function == 'VERSION':
              # Version of ReqHandle.
              self.printLn("N", "Version: " + version)
              self.updateResults({}, reset=1)
          else:
              # Some type of function/subfunction invocation.
              if self.function in self.funcHandler:
                  # Invoke the functions doIt routine to route to the
                  # appropriate subfunction.
                  self.funcHandler[self.function][3](self)
              else:
                  # Unrecognized function
                  msg = msgs.msg['0007'][1] % (modId, self.function)
                  self.printLn("ES", msg)
                  self.updateResults(msgs.msg['0007'][0])
  
          return self.results