code: def paths_from_env(prefix=None, names=None):
      
  
  
      def expand_path(path):
          """Expands variables in 'path' and turns it into absolute path"""
  
          return os.path.abspath(os.path.expanduser(os.path.expandvars(path)))
  
  
      if prefix is None:
          prefix = "CIJ"
      if names is None:
          names = [
              "ROOT", "ENVS", "TESTPLANS", "TESTCASES", "TESTSUITES", "MODULES",
              "HOOKS", "TEMPLATES"
          ]
  
      conf = {v: os.environ.get("_".join([prefix, v])) for v in names}
  
      for env in (e for e in conf.keys() if e[:len(prefix)] in names and conf[e]):
          conf[env] = expand_path(conf[env])
          if not os.path.exists(conf[env]):
              err("%s_%s: %r, does not exist" % (prefix, env, conf[env]))
  
      return conf
docs: Construct dict of paths from environment variables