练习解决方案：《飞翔的马戏团》演员名单

def create_cast_list(filename):
    cast_list = []
    # use with to open the file filename
    with open(filename) as f:
    # use the for loop syntax to process each line        
    # and add the actor name to cast_list
        for line in f:
            line_data = line.split(',')
            cast_list.append(line_data[0])
    return cast_list