如何将字典转换为一串关键字参数？

**kw

kw

kw

str(kw)

str(dict)

obj.method(name='name', test='test', relation = [('id','=',1)])

"name='name', test='test', relation = [('id','=',1)]"

def somestring(**kwargs):
  return ', '.join('%s=%r' % x for x in kwargs.iteritems())