A multi-purpose function that can be used as a normal function,
a class decorator, or a function decorator.Parameters:
input_data (Union[str, type, Callable]): - If a string is provided, it should be a JSON-encoded string that will be converted into a BaseModel. - If a function is provided, it will be decorated such that its arguments are converted into a BaseModel. - If a BaseModel class is provided, it will be returned directly.
Returns:Type[BaseModel]: The BaseModel class that will be used to
structure the input data.