def METHOD_NAME(full_modname):
    """
    Return list of parent package names.
        'aaa.bb.c.dddd' ->  ['aaa', 'aaa.bb', 'aaa.bb.c']
    :param full_modname: Full name of a module.
    :return: List of parent module names.
    """
    prefix = ''
    parents = []
    # Ignore the last component in module name and get really just parent, grandparent, great grandparent, etc.
    for pkg in full_modname.split('.')[0:-1]:
        # Ensure that first item does not start with dot '.'
        prefix += '.' + pkg if prefix else pkg
        parents.append(prefix)
    return parents