externalise order form: create script orderform that orders the infos in a form file

orderform.py

@@ -0,0 +1,53 @@
+#! /usr/bin/python3
+# -*- coding: UTF-8 -*-
+
+"""Order the infos in a form file.
+
+Input is:
+    a config file
+
+Output is:
+    the same config file ordered as described in readformdata
+
+"""
+
+import os.path
+import argparse
+import readformdata
+
+
+def parse():
+    """Create the argument parser (including the help) and parse the arguments.
+
+    Options/ Arguments:
+        formfile
+
+    """
+    parser = argparse.ArgumentParser(
+        description="Order a form file.")
+    parser.add_argument("formfile",
+                        help="The form file to be ordered.")
+    parser.add_argument("--output", default=None,  # nargs=1,
+                        # None = input
+                        help="The newly created file." +
+                        " (Default: input is overridden.)")
+    args = vars(parser.parse_args())
+    args["output"] = (args["formfile"]
+                      if args["output"] is None
+                      else args["output"])
+    for f in (args["formfile"], args["output"]):
+        if not os.path.isfile(f):
+            parser.print_help()
+            raise argparse.ArgumentTypeError(f + " is not a valid file.")
+    return args
+
+
+if __name__ == "__main__":
+    try:
+        arguments = parse()
+    except argparse.ArgumentTypeError as e:
+        print("Error while parsing the command line arguments:\n", e)
+    else:
+        config = readformdata.listFields([], arguments["formfile"])
+        # make dict out of [[]] list + dict from config file
+        readformdata.writeFields(config, arguments["output"])