Isn't the biggest difference between Python 2 and 3 and handling of Unicode? That's what motivated the break in compatibility in the first place.

But in Skulpt the strings don't quite work like any of the Python versions.

Python 2 has a combined str/bytes type and a separate Unicode string type:

  >>> type("hello") is type(u"你好")
  False
  >>> len(u"你好")
  2
  >>> len("你好")
  6

...whereas in Python 3 the str type is Unicode and the "bytes" type is a completely separate thing:

  >>> type("hello") is type(u"你好")
  True
  >>> len(u"你好")
  2
  >>> len("你好")
  2

Skulpt actually seems to work more like Python 3, except that 1) there is no way at all to work with bytes (that I can find), e.g. no encode/decode methods, and it 2) requires the "u" prefix if literals contain non-ASCII characters, even though the type of the resulting string is the same as without the prefix:

  >>> type("hello") is type(u"你好")
  True
  >>> len(u"你好")
  2
  >>> len("你好")
  SyntaxError: invalid string (possibly contains a unicode character) on line 1