code: def set(self, mode=None):
          
          # Detect from the environment if no mode given (only once)
          if mode is None:
              # Nothing to do if already detected
              if self._mode is not None:
                  return
              # Detect from the environment variable COLOR
              try:
                  mode = int(os.environ["COLOR"])
              except StandardError:
                  mode = COLOR_AUTO
          elif mode < 0 or mode > 2:
              raise RuntimeError("Invalid color mode '{0}'".format(mode))
          self._mode = mode
          log.debug(
              "Coloring {0} ({1})".format(
                  "enabled" if self.enabled() else "disabled",
                  self.MODES[self._mode]))
docs: Set the coloring mode
  
          If enabled, some objects (like case run Status) are printed in color
          to easily spot failures, errors and so on. By default the feature is
          enabled when script is attached to a terminal. Possible values are::
  
              COLOR=0 ... COLOR_OFF .... coloring disabled
              COLOR=1 ... COLOR_ON ..... coloring enabled
              COLOR=2 ... COLOR_AUTO ... if terminal attached (default)
  
          Environment variable COLOR can be used to set up the coloring to the
          desired mode without modifying code.