options.py 文件源码

def set(self, value):
        if self.multiple:
            if not isinstance(value, list):
                raise Error("Option %r is required to be a list of %s" %
                            (self.name, self.type.__name__))
            for item in value:
                if item is not None and not isinstance(item, self.type):
                    raise Error("Option %r is required to be a list of %s" %
                                (self.name, self.type.__name__))
        else:
            if value is not None and not isinstance(value, self.type):
                raise Error("Option %r is required to be a %s (%s given)" %
                            (self.name, self.type.__name__, type(value)))
        self._value = value
        if self.callback is not None:
            self.callback(self._value)

    # Supported date/time formats in our options