Add CA running script

Adding a CA-based running script.

I also noticed that the instructions had incorrect capitalisation (I think) for the athena run command and the RootStreamName was not set in the NTuple making algorithm. This didn't matter for now because it isn't used for any outputs but still better to fix.

source/NtupleMaker/python/run.py

+import argparse
+
+parser = argparse.ArgumentParser()
+parser.add_argument("input_files", nargs="+", help="The input files to run over")
+parser.add_argument(
+    "-o", "--output", default="myfile.root", help="The output ROOT File"
+)
+parser.add_argument(
+    "-e",
+    "--n-events",
+    type=int,
+    default=-1,
+    help="The number of events to run over, -1 means all",
+)
+parser.add_argument(
+    "-l",
+    "--log-level",
+    type=str.upper,
+    default="INFO",
+    choices=("VERBOSE", "DEBUG", "INFO", "WARNING", "ERROR"),
+    help="The message level to set",
+)
+args = parser.parse_args()
+
+from AthenaConfiguration.AllConfigFlags import ConfigFlags
+from AthenaConfiguration.ComponentFactory import CompFactory
+from AthenaConfiguration.MainServicesConfig import MainServicesCfg
+from AthenaCommon import Constants
+from AthenaRootComps.xAODEventSelectorConfig import xAODReadCfg
+
+# Setup the input
+ConfigFlags.Input.Files = args.input_files
+ConfigFlags.Exec.OutputLevel = getattr(Constants, args.log_level)
+ConfigFlags.Exec.MaxEvents = args.n_events
+ConfigFlags.lock()
+
+acc = MainServicesCfg(ConfigFlags)
+acc.merge(xAODReadCfg(ConfigFlags))
+# Suppress the printing on every event
+acc.getService(acc.getAppProps()["EventLoop"]).EventPrintoutInterval = 1000
+# Add our output stream to the hist svc
+acc.addService(
+    CompFactory.THistSvc(Output=[f"MYSTREAM DATAFILE='{args.output}' OPT='RECREATE'"])
+)
+# Add our algorithm
+acc.addEventAlgo(
+    CompFactory.NtupleMakerAlg(
+        "NtupleMakerAlg", ascii_file="NtupleMaker/cow.txt", RootStreamName="MYSTREAM"
+    )
+)
+# Run the job
+acc.run()