code: def _make_command_filename(self, exe):
          
  
          outfn = os.path.join(self.commons['cmddir'], self.name(),
                               self._mangle_command(exe))
  
          # check for collisions
          if os.path.exists(outfn):
              inc = 2
              while True:
                  newfn = "%s_%d" % (outfn, inc)
                  if not os.path.exists(newfn):
                      outfn = newfn
                      break
                  inc += 1
  
          return outfn
docs: The internal function to build up a filename based on a command.