Adds command to get admin code

bookwyrm/management/commands/admin_code.py

@@ -0,0 +1,18 @@
+""" Get your admin code to allow install """
+from django.core.management.base import BaseCommand
+
+from bookwyrm import models
+
+def get_admin_code():
+    """get that code"""
+    return models.SiteSettings.objects.get().admin_code
+
+class Command(BaseCommand):
+    """command-line options"""
+
+    help = "Gets admin code for configuring BookWyrm"
+
+    # pylint: disable=unused-argument
+    def handle(self, *args, **options):
+        """execute init"""
+        self.stdout.write(get_admin_code())