code: def _handle_default(value, script_name):
      
      if value:
          return value
  
      installed_script = which("pulsar-%s" % script_name.replace("_", "-"))
      if installed_script:
          return installed_script
      else:
          return "scripts/%s.bash" % script_name
docs: There are two potential variants of these scripts,
      the Bash scripts that are meant to be run within PULSAR_ROOT
      for older-style installs and the binaries created by setup.py
      as part of a proper pulsar installation.
  
      This method first looks for the newer style variant of these
      scripts and returns the full path to them if needed and falls
      back to the bash scripts if these cannot be found.