docs: def convert_argmap(self, query):
          """Converts the query string of an URL to a map.
  
          Parameters
          ----------
          query : string
              The URL to parse.
  
          Returns
          -------
          A map object containing all fields as keys with their value. Fields
          without '=' in the URL are interpreted as flags and the value is set
          to True.
          """
          res = {}
          if isinstance(query, bytes):
              query = query.decode('utf8')
          for section in query.split('&'):
              eqs = section.split('=', 1)
              name = urlparse_unquote(eqs[0])
              if len(eqs) > 1:
                  res[name] = urlparse_unquote(eqs[1])
              else:
                  res[name] = True
          return res