urllib.urlencode doesn't like unicode values: how about this workaround?

If I have an object like:

d = {'a':1, 'en': 'hello'}

...then I can pass it to urllib.urlencode, no problem:

percent_escaped = urlencode(d)
print percent_escaped

But if I try to pass an object with a value of type unicode, game over:

d2 = {'a':1, 'en': 'hello', 'pt': u'olá'}
percent_escaped = urlencode(d2)
print percent_escaped # This fails with a UnicodeEncodingError

So my question is about a reliable way to prepare an object to be passed to urlencode.

I came up with this function where I simply iterate through the object and encode values of type string or unicode:

def encode_object(object):
  for k,v in object.items():
    if type(v) in (str, unicode):
      object[k] = v.encode('utf-8')
  return object

This seems to work:

d2 = {'a':1, 'en': 'hello', 'pt': u'olá'}
percent_escaped = urlencode(encode_object(d2))
print percent_escaped

And that outputs a=1&en=hello&pt=%C3%B3la, ready for passing to a POST call or whatever.

But my encode_object function just looks really shaky to me. For one thing, it doesn't handle nested objects.

For another, I'm nervous about that if statement. Are there any other types that I should be taking into account?

And is comparing the type() of something to the native object like this good practice?

type(v) in (str, unicode) # not so sure about this...

Thanks!