The create ece2cmor3 environment process with mamba hangs

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While trying to recreate the ece2cmor conda environment I found out that when running mamba for that the process is hanging. First I tried with my previous mamba install thereafter I reinstalled mamba itself as well, but it did not make a difference. In any case it hangs when executing:

mamba env create -f environment.yml

Unfortunately no clue or message was provided. Only about at most two weeks earlier this problem did not occur. I encountered it while trying to follow the latest CMIP7 data request software release (accompanying the latest CMIP7 data request release).

After many attempts in the wrong direction I found out that the pyngl package causes the trouble. When taking it off from the package list in the environment.yml the ece2cmor3 environment can be created again. However, then the ece2cmor3 install fails because the pyngl package is missing. With taking off the import Ngl lines the ece2cmor3 install can be continued, but cmorisation of TM5 output will fail because of the Ngl.vinth2p call in tm52cmor.py

Note that with taking of the pyngl package, the use of the latest python version is not longer blocked, resulting in a Python 3.14.2 version now (see also #828 and #731).