Import name as a module and return a list of all classes defined in that
    module. superclasses should be a tuple of valid superclasses to import,
    this defaults to (Plugin,).

def import_plugin(name, superclasses=None):
    """Import name as a module and return a list of all classes defined in that
    module. superclasses should be a tuple of valid superclasses to import,
    this defaults to (Plugin,).
    """
    plugin_fqname = "sos.plugins.%s" % name
    if not superclasses:
        superclasses = (Plugin,)
    return import_module(plugin_fqname, superclasses)