Various errors related to incorrect recognition of the ISO-2 country code "NA" as NaN value

[doneachh]

Checklist

• I am using the current main branch or the latest release. Please indicate.
• I am running on an up-to-date pypsa-africa environment. Update via conda env update -f envs/environment.yaml.

Describe the Bug

Country Code "NA" gets recognized as NaN Value

Error Message

Traceback (most recent call last):
File "/mnt/c/Users/aca39878/Documents/Git/Namibia/pypsa-earth-sec/.snakemake/scripts/tmpaobgxggx.build_industry_demand.py", line 158, in
AL_prod_tom = AL["production[ktons/a]"].loc[countries]
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/site-packages/pandas/core/indexing.py", line 1153, in getitem
return self._getitem_axis(maybe_callable, axis=axis)
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/site-packages/pandas/core/indexing.py", line 1382, in _getitem_axis
return self._getitem_iterable(key, axis=axis)
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/site-packages/pandas/core/indexing.py", line 1322, in _getitem_iterable
keyarr, indexer = self._get_listlike_indexer(key, axis)
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/site-packages/pandas/core/indexing.py", line 1520, in _get_listlike_indexer
keyarr, indexer = ax._get_indexer_strict(key, axis_name)
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/site-packages/pandas/core/indexes/base.py", line 6115, in _get_indexer_strict
self._raise_if_missing(keyarr, indexer, axis_name)
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/site-packages/pandas/core/indexes/base.py", line 6176, in _raise_if_missing
raise KeyError(f"None of [{key}] are in the [{axis_name}]")
KeyError: "None of [Index(['NA'], dtype='object', name='country')] are in the [index]"
[Fri Jan 26 14:22:07 2024]
INFO:snakemake.logging:[Fri Jan 26 14:22:07 2024]
Error in rule build_industry_demand:
jobid: 18
input: resources/demand/industrial_distribution_key_elec_s_10.csv, resources/demand/base_industry_totals_2030_DF.csv, data/industrial_database.csv, data/costs_2030.csv
output: resources/demand/industrial_energy_demand_per_node_elec_s_10_2030_DF.csv

ERROR:snakemake.logging:Error in rule build_industry_demand:
jobid: 18
input: resources/demand/industrial_distribution_key_elec_s_10.csv, resources/demand/base_industry_totals_2030_DF.csv, data/industrial_database.csv, data/costs_2030.csv
output: resources/demand/industrial_energy_demand_per_node_elec_s_10_2030_DF.csv

RuleException:
CalledProcessError in file /mnt/c/Users/aca39878/Documents/Git/Namibia/pypsa-earth-sec/Snakefile, line 681:
Command 'set -euo pipefail; /home/aca39878/anaconda3/envs/pypsa-earth/bin/python3.10 /mnt/c/Users/aca39878/Documents/Git/Namibia/pypsa-earth-sec/.snakemake/scripts/tmpaobgxggx.build_industry_demand.py' returned non-zero exit status 1.
File "/mnt/c/Users/aca39878/Documents/Git/Namibia/pypsa-earth-sec/Snakefile", line 681, in __rule_build_industry_demand
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/concurrent/futures/thread.py", line 58, in run
ERROR:snakemake.logging:RuleException:
CalledProcessError in file /mnt/c/Users/aca39878/Documents/Git/Namibia/pypsa-earth-sec/Snakefile, line 681:
Command 'set -euo pipefail; /home/aca39878/anaconda3/envs/pypsa-earth/bin/python3.10 /mnt/c/Users/aca39878/Documents/Git/Namibia/pypsa-earth-sec/.snakemake/scripts/tmpaobgxggx.build_industry_demand.py' returned non-zero exit status 1.
File "/mnt/c/Users/aca39878/Documents/Git/Namibia/pypsa-earth-sec/Snakefile", line 681, in __rule_build_industry_demand
File "/home/aca39878/anaconda3/envs/pypsa-earth/lib/python3.10/concurrent/futures/thread.py", line 58, in run
Shutting down, this might take some time.
WARNING:snakemake.logging:Shutting down, this might take some time.
Exiting because a job execution failed. Look above for error message

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