def METHOD_NAME(self, proposal):
    """Enforce min <= value <= max"""
    max = proposal["value"]
    if max is None:
        return max
    max = self._validate_tz(max)
    if self.min and max < self.min:
        raise TraitError("setting max < min")
    if self.value and max < self.value:
        self.value = max
    return max