def _remove_type_str_from_arg_str(arg_str):
    """
    Remove the string of type information from the argument string.

    Parameters
    ----------
    arg_str : str
        The target argument string.

    Returns
    -------
    after_arg_str : str
        String after type information has been removed.
    """
    is_in = ':' in arg_str
    if not is_in:
        return arg_str
    after_arg_str = arg_str.split(':')[0]
    is_in = '=' in arg_str
    if is_in:
        after_arg_str += '=%s' % arg_str.split('=')[1]
    after_arg_str = after_arg_str.strip()
    return after_arg_str
