docs: def parse_doc(doc):
      """
      Parse docstrings to dict, it should look like:
        key: value
      """
      if not doc:
          return {}
      out = {}
      for s in doc.split('\n'):
          s = s.strip().split(':', maxsplit=1)
          if len(s) == 2:
              out[s[0]] = s[1]
      return out