Put `func` with `args` and `kwargs` in `self.flow_func` for later.

def coord(self, func:CoordFunc, *args, **kwargs)->'ImagePoints':
        "Put `func` with `args` and `kwargs` in `self.flow_func` for later."
        if 'invert' in kwargs: kwargs['invert'] = True
        else: warn(f"{func.__name__} isn't implemented for {self.__class__}.")
        self.flow_func.append(partial(func, *args, **kwargs))
        return self