code: def dict2cols(d, spaces=2, separator=' '):
      
      if len(d) == 0:
          return ''
      s = ''
      maxlen = max([len(k) for k in d.keys()])
      fmt_str = '{k:' + separator + '<' + str(maxlen + spaces) + '}{v}\n'
      for k in sorted(d.keys()):
          s += fmt_str.format(
              k=k,
              v=d[k],
          )
      return s
docs: Take a dict of string keys and string values, and return a string with
      them formatted as two columns separated by at least ``spaces`` number of
      ``separator`` characters.
  
      :param d: dict of string keys, string values
      :type d: dict
      :param spaces: number of spaces to separate columns by
      :type spaces: int
      :param separator: character to fill in between columns
      :type separator: str