code: def print_defaults():
      
      maxlen = max([len(x) for x in DEFAULTS])
      for key in DEFAULTS:
          value = DEFAULTS[key]
          if isinstance(value, (list, set)):
              value = ', '.join(value)
          print "%*s: %s" % (maxlen, key, value)
docs: Pretty-print the contents of :data:`DEFAULTS`