def __init__(self, name, host='127.0.0.1', port=27017):
        self.name = name
        self.host = host
        self.port = port
def __init__(
        self, minimum=None, maximum=None, choices=None, optional=False
    ):
        self._required = not optional
        self._minimum = minimum
        self._maximum = maximum
        self._choices = choices