Unable to install both returns and classes together

[adam-stokes]

Bug report

What's wrong

Just doing a simple poetry add returns and poetry add classes results in:

 Because no versions of classes match >0.4.0,<0.5.0
   and classes (0.4.0) depends on typing_extensions (>=3.10,<4.0), classes (>=0.4.0,<0.5.0) requires typing_extensions (>=3.10,<4.0).
  And because returns (0.19.0) depends on typing-extensions (>=4.0,<5.0)
   and no versions of returns match >0.19.0,<0.20.0, classes (>=0.4.0,<0.5.0) is incompatible with returns (>=0.19.0,<0.20.0).
  So, because ogc depends on both returns (^0.19.0) and classes (^0.4.0), version solving failed.

How is that should be

Should I be able to run both of these libraries together? If so, maybe just a typing-extensions version update is needed?

System information

• python version: 3.9
• classes version: 0.4.0
• returns version: 0.19.0
• mypy version: 0.941