def get_formatter(name):
    """Return the named formatter function.  See the function
    "set_formatter" for details.
    """
    if name in ('self', 'instance', 'this'):
        return af_self
    elif name == 'class':
        return af_class
    elif name in ('named', 'param', 'parameter'):
        return af_named
    elif name in ('default', 'optional'):
        return af_default
#    elif name in ('anonymous', 'arbitrary', 'unnamed'):
#        return af_anonymous
    elif name in ('keyword', 'pair', 'pairs'):
        return af_keyword
    else:
        raise ValueError('unknown trace formatter %r' % name)
Return the named formatter function.  See the function
    "set_formatter" for details.