def format_inheritance_flags(parent):
    """Return a human readable string of inheritance flags"""
    flags = ''
    for code, expr in (('M', parent['maxdepth'] is not None), ('F', parent[
        'pkg_filter']), ('I', parent['intransitive']), ('N', parent[
        'noconfig'])):
        if expr:
            flags += code
        else:
            flags += '.'
    return flags
