Add generic run script

tests/run_script.py

@@ -0,0 +1,26 @@
+"""A generic run script for testing changes to `e3sm_to_cmip` at runtime.
+
+This script is useful for testing code changes to `e3sm_to_cmip` without having
+to install the package. It imports the `main` function from the `__main__`
+module and passes a list of arguments to it. The arguments are the same as those
+passed to the command line interface (CLI) of `e3sm_to_cmip`.
+The script can be run from the command line or an IDE.
+"""
+from e3sm_to_cmip.__main__ import main
+
+args = [
+    "--var-list",
+    'pfull, phalf, tas, ts, psl, ps, sfcWind, huss, pr, prc, prsn, evspsbl, tauu, tauv, hfls, clt, rlds, rlus, rsds, rsus, hfss, cl, clw, cli, clivi, clwvi, prw, rldscs, rlut, rlutcs, rsdt, rsuscs, rsut, rsutcs, rtmt, abs550aer, od550aer, rsdscs, hur',
+    "--input",
+    "/lcrc/group/e3sm/e3sm_to_cmip/input/atm-unified-eam-ncclimo",
+    "--output",
+    "../qa/tmp",
+    "--tables-path",
+    "/lcrc/group/e3sm/e3sm_to_cmip/cmip6-cmor-tables/Tables/",
+    "--user-metadata",
+    "/lcrc/group/e3sm/e3sm_to_cmip/template.json",
+    "--serial"
+]
+
+# `main()` creates an `E3SMtoCMIP` object and passes `args` to it, which sets the object parameters to execute a run.
+main(args)