Replace environment variable for TW instance ID with optional parameter

docker-compose.yml

@@ -11,7 +11,6 @@ services:
     - CLIENT_ID
     - TOKEN
     - LOG_CHANNEL
-    - TUPPERWARE_ID
     - "DATABASE_USER=postgres"
     - "DATABASE_PASS=postgres"
     - "DATABASE_NAME=postgres"

src/pluralkit/bot/commands/import_commands.py

@@ -1,4 +1,3 @@
-import os
 from datetime import datetime
 
 from pluralkit.bot.commands import *
@@ -13,12 +12,19 @@ async def import_tupperware(ctx: CommandContext):
     # Check if there's a Tupperware bot on the server
     # Main instance of TW has that ID, at least
     tupperware_id = 431544605209788416
-    if "TUPPERWARE_ID" in os.environ:
+    if ctx.has_next():
-        tupperware_id = int(os.environ["TUPPERWARE_ID"])
+        try:
+            id_str = ctx.pop_str()
+            tupperware_id = int(id_str)
+        except ValueError:
+            raise CommandError("'{}' is not a valid ID.".format(id_str))
 
     tupperware_member = ctx.message.guild.get_member(tupperware_id)
     if not tupperware_member:
-        raise CommandError("This command only works in a server where the Tupperware bot is also present.")
+        raise CommandError(
+            """This command only works in a server where the Tupperware bot is also present. 
+
+If you're trying to import from a Tupperware instance other than the main one (which has the ID 431544605209788416), pass the ID of that instance as a parameter.""")
 
     # Make sure at the bot has send/read permissions here
     channel_permissions = ctx.message.channel.permissions_for(tupperware_member)