def _determine_data_format(lines):
    """
    Determine the format of the data block in the .pypeit file.

    The test used in this function is pretty basic.  A table format is
    assumed if the first character in *any* line is `|`.

    Args:
        lines (:obj:`list`):
            The list of lines read from the data block of the pypeit
            file.
    
    Returns:
        str: The syntax of the data files to read::

            'raw': A (list of) file roots to be read or found using
            `glob`.

            'table': ASCII output of an astropy.table.Table

    """
    for l in lines:
        if l[0] == '|':
            return 'table'
    return 'raw'