.get_params(), from the source code 24, requires lower and upper bounds for each parameter (brightness, contrast, saturation and hue), as well as each parameter to be set, as they don’t have default values.
However, the ColorJitter.__init__() method accepts both int and listor tuple input arguments, which are then properly formatted with the private method _check_input().
Why do you want to use .get_params() instead of the more convenient form ColorJitter(...) ?