Add arguments

threads.py

@@ -1,13 +1,29 @@
-from datetime import datetime, timedelta
+import config
 from mastodon import Mastodon
 from treelib import Node, Tree
+from datetime import datetime, timedelta
+from urllib.parse import urlparse
+import argparse
 from bs4 import BeautifulSoup
 
-import config
+#  Take a command line argument. e.g. python3 threads.py https://mastodon.example/@me@somewhere/1234
+parser = argparse.ArgumentParser(description='Display a tree based on a Mastodon conversation.')
+parser.add_argument('url', metavar='URl', type=str, help='A URl of a post on your instance of Mastodon')
+args = parser.parse_args()
+path = urlparse(args.url).path
+path_list = path.split("/")
+path_id = path_list[-1]
 
-#  Status ID
-#  This is the ID from *your* instance
-status_id =  109343943300929632
+if path_id.isdigit() :
+   #  Status ID
+   #  This is the ID from *your* instance
+   status_id = int(path_id)
+else :
+   print("Hmmm... That doesn't look like a valid Mastodon Status URl.\n" +
+         "It should look like https://mastodon.example/@me@somewhere/1234\n" +
+         "The last part of the URl must be the status ID, which is a number."
+   )
+   exit()
 
 #  Set up access
 mastodon = Mastodon( api_base_url=config.instance, access_token=config.access_token )