Add rule create_scenarios that runs config/create_scenarios.py on request

Snakefile

@@ -93,6 +93,13 @@ rule all:
     default_target: True
 
 
+rule create_scenarios:
+    output:
+        config["run"]["scenarios"]["file"],
+    script:
+        "config/create_scenarios.py"
+
+
 rule purge:
     run:
         import builtins

config/create_scenarios.py

@@ -1,11 +1,15 @@
 # -*- coding: utf-8 -*-
-# SPDX-FileCopyrightText: : 2017-2023 The PyPSA-Eur Authors
+# SPDX-FileCopyrightText: : 2023-2024 The PyPSA-Eur Authors
 #
 # SPDX-License-Identifier: MIT
 
 # This script helps to generate a scenarios.yaml file for PyPSA-Eur.
 # You can modify the template to your needs and define all possible combinations of config values that should be considered.
 
+if "snakemake" in globals():
+    filename = snakemake.output[0]
+else:
+    filename = "../config/scenarios.yaml"
 
 import itertools
 
@@ -14,23 +18,23 @@ import itertools
 template = """
 scenario{scenario_number}:
     config_section:
-        config_value: {config_value}
-
+        config_key: {config_value}
     config_section2:
         config_key2: {config_value2}
 """
 
 # Define all possible combinations of config values.
 # This must define all config values that are used in the template.
-config_values = dict(config_values=["true", "false"], config_values2=[1, 2, 3, 4, 5])
+config_values = dict(
+    config_value=["true", "false"],
+    config_value2=[1, 2, 3, 4]
+)
 
 combinations = [
     dict(zip(config_values.keys(), values))
     for values in itertools.product(*config_values.values())
 ]
 
-# write the scenarios to a file
-filename = "../config/scenarios.yaml"
 with open(filename, "w") as f:
     for i, config in enumerate(combinations):
         f.write(template.format(scenario_number=i, **config))