Removing `more_itertools` dependency.
Author: Narsil
Pull request: yes

# What does this PR do?

Removes `more_itertools` optional dependency.
Fixes  #20508

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Fixes # (issue)


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Models:

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Library:

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Comments:
_The documentation is not available anymore as the PR was closed or merged._

I don't think the failure is linked in any way to this PR, is it ?