You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: modelPreprocessMovie.m
    path of file: ./repos/ciatah/@ciatah
    
    the code of the file until where you have to start completion: function obj = modelPreprocessMovie(obj)
	% Controller for pre-processing movies, mainly aimed at calcium imaging data. Wrapper for modelPreprocessMovieFunction.
	% Biafra Ahanonu
	% started 2013.11.09 [10:46:23]

	% changelog
		% 2021.08.10 [09:57:36] - Updated to handle CIAtah v4.0 switch to all functions inside ciapkg package.


    
function obj = modelPreprocessMovie(obj)
	% Controller for pre-processing movies, mainly aimed at calcium imaging data. Wrapper for modelPreprocessMovieFunction.
	% Biafra Ahanonu
	% started 2013.11.09 [10:46:23]

	% changelog
		% 2021.08.10 [09:57:36] - Updated to handle CIAtah v4.0 switch to all functions inside ciapkg package.

	import ciapkg.api.* % import CIAtah functions in ciapkg package API.

	% verify that there are folders present
	if isempty(obj.inputFolders)
		uiwait(ciapkg.overloaded.msgbox('Please run modelAddNewFolders to add folders to the object','Success','modal'));
		return
	end