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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def auto_complete_paths(current, completion_type):
 """If ``completion_type`` is ``file`` or ``path``, list all regular files and directories starting with ``current``; otherwise only list directories starting with ``current``. :param current: The word to be completed :param completion_type: path completion type(`file`, `path` or `dir`)i :return: A generator of regular files and/or directories """

    directory, filename = os.path.split(current)
    current_path = os.path.abspath(directory)
    # Don't complete paths if they can't be accessed
    if not os.access(current_path, os.R_OK):
        return
    filename = os.path.normcase(filename)
    # list all files that start with ``filename``
    file_list = (x for x in os.listdir(current_path)
                 if os.path.normcase(x).startswith(filename))
    for f in file_list:
        opt = os.path.join(current_path, f)
        comp_file = os.path.normcase(os.path.join(directory, f))
        # complete regular files when there is not ``<dir>`` after option
        # complete directories when there is ``<file>``, ``<path>`` or
        # ``<dir>``after option
        if completion_type != 'dir' and os.path.isfile(opt):
            yield comp_file
        elif os.path.isdir(opt):
            yield os.path.join(comp_file, '')