docs: def set(self, key, value):
          """
          Function deeply sets the key with "." notation
  
          Args
          ----
            key (string): A key with the "." notation.
            value (unknown type): A dict or a primitive type.
          """
          target = self.registrar
          for element in key.split('.')[:-1]:
              target = target.setdefault(element, dict())
          target[key.split(".")[-1]] = value