mypy 1.4.0 is not compatible with typing-extensions 3.10 version

[olgasentemova]

Bug Report

mypy 1.4.0 is not compatible with typing-extensions 3.10 version.

To Reproduce
Install mypy 1.4.0 on an environment where typing_extensions library has a 3.10 version
Python version is used 3.11

 pip3 show typing_extensions                    
Name: typing-extensions
Version: 3.10.0.2
Summary: Backported and Experimental Type Hints for Python 3.5+
Home-page: https://github.com/python/typing/blob/master/typing_extensions/README.rst
Author: Guido van Rossum, Jukka Lehtosalo, Łukasz Langa, Michael Lee
Author-email: [email protected]
License: PSF
Location: /usr/local/lib/python3.11/site-packages
Requires: 
Required-by: mypy

pip3 list | grep mypy
mypy              1.4.0
mypy-extensions   1.0.0

run
mypy .
Expected Behavior

mypy starts and runs the analysis

Actual Behavior

mypy .               
Traceback (most recent call last):
  File "/usr/local/bin/mypy", line 5, in <module>
    from mypy.__main__ import console_entry
  File "/usr/local/lib/python3.11/site-packages/mypy/__main__.py", line 9, in <module>
    from mypy.main import main, process_options
  File "mypy/main.py", line 14, in <module>
  File "mypy/build.py", line 47, in <module>
  File "mypy/semanal_main.py", line 35, in <module>
  File "mypy/checker.py", line 27, in <module>
  File "mypy/checkexpr.py", line 13, in <module>
  File "mypy/applytype.py", line 5, in <module>
  File "mypy/subtypes.py", line 8, in <module>
  File "mypy/constraints.py", line 9, in <module>
  File "mypy/typeops.py", line 13, in <module>
  File "mypy/copytype.py", line 5, in <module>
  File "mypy/types.py", line 20, in <module>
    def f():
ImportError: cannot import name 'Self' from 'typing_extensions' (/usr/local/lib/python3.11/site-packages/typing_extensions.py)

Your Environment

• Mypy version used: 1.4.0.
• Mypy command-line flags: none
• Mypy configuration options from mypy.ini (and other config files): none
• Python version used: Python 3.11.4 (main, Jun 15 2023, 07:29:58) [Clang 14.0.3 (clang-1403.0.22.14.1)] on darwin

[cdce8p]

Yeah. Mypy started using Self which is only available in typing_extensions>=4.0.0. I'll open a PR shortly to bump the requirement. In the meantime, you can update typing_extensions manually.

[cdce8p]

Just a heads up. We just discovered another new import. You'll need to use at least version 4.1.0.

[AlexWaygood]

Just a heads up. We just discovered another new import. You'll need to use at least version 4.1.0.

(The import in question is is_typeddict, which is new in typing_extensions 4.1.0 -- we import is_typeddict in mypy/stubtest.py. But the is_typeddict import in stubtest has actually been there for a while, I think -- the reason it's never come up before now is probably because only a subset of mypy users are stubtest users :)