@staticmethod
def get_braces_content(data):
    """extract data from within comma separated, round-braces string
        return list of strings

        >>> ASDL.get_braces_content('(a,b,c)')
        ['a', 'b', 'c']
        """
    left_brace = data.split('(')
    if len(left_brace) > 1:
        return left_brace[1].split(')')[0].split(',')
    return []
