diff --git a/src/allmydata/scripts/common.py b/src/allmydata/scripts/common.py
index 34266ee72..572048f71 100644
--- a/src/allmydata/scripts/common.py
+++ b/src/allmydata/scripts/common.py
@@ -4,15 +4,19 @@ import os, sys, urllib, textwrap
 import codecs
 from os.path import join
 
+from yaml import (
+    safe_dump,
+)
+
 # Python 2 compatibility
 from future.utils import PY2
 if PY2:
     from future.builtins import str  # noqa: F401
 
-# On Python 2 this will be the backported package:
-from configparser import NoSectionError
-
 from twisted.python import usage
+from twisted.python.filepath import FilePath
+
+
 
 from allmydata.util.assertutil import precondition
 from allmydata.util.encodingutil import unicode_to_url, quote_output, \
@@ -115,6 +119,22 @@ class NoDefaultBasedirOptions(BasedirOptions):
 DEFAULT_ALIAS = u"tahoe"
 
 
+def write_introducer(basedir, petname, furl):
+    """
+    Overwrite the node's ``introducers.yaml`` with a file containing the given
+    introducer information.
+    """
+    FilePath(basedir).child(b"private").child(b"introducers.yaml").setContent(
+        safe_dump({
+            "introducers": {
+                petname: {
+                    "furl": furl.decode("ascii"),
+                },
+            },
+        }).encode("ascii"),
+    )
+
+
 def get_introducer_furl(nodedir, config):
     """
     :return: the introducer FURL for the given node (no matter if it's
diff --git a/src/allmydata/test/common.py b/src/allmydata/test/common.py
index 8eab155b0..cbe4d768c 100644
--- a/src/allmydata/test/common.py
+++ b/src/allmydata/test/common.py
@@ -32,10 +32,6 @@ import attr
 
 import treq
 
-from yaml import (
-    safe_dump,
-)
-
 from zope.interface import implementer
 
 from testtools import (
@@ -85,6 +81,9 @@ from allmydata.client import (
     config_from_string,
     create_client_from_config,
 )
+from allmydata.scripts.common import (
+    write_introducer,
+    )
 
 from ..crypto import (
     ed25519,
@@ -104,22 +103,6 @@ EMPTY_CLIENT_CONFIG = config_from_string(
 )
 
 
-def write_introducer(basedir, petname, furl):
-    """
-    Overwrite the node's ``introducers.yaml`` with a file containing the given
-    introducer information.
-    """
-    FilePath(basedir).child(b"private").child(b"introducers.yaml").setContent(
-        safe_dump({
-            "introducers": {
-                petname: {
-                    "furl": furl.decode("ascii"),
-                },
-            },
-        }).encode("ascii"),
-    )
-
-
 @attr.s
 class MemoryIntroducerClient(object):
     """
diff --git a/src/allmydata/test/test_client.py b/src/allmydata/test/test_client.py
index b76047be0..7fb82c262 100644
--- a/src/allmydata/test/test_client.py
+++ b/src/allmydata/test/test_client.py
@@ -58,6 +58,9 @@ from allmydata.util import (
 from allmydata.util.fileutil import abspath_expanduser_unicode
 from allmydata.interfaces import IFilesystemNode, IFileNode, \
      IImmutableFileNode, IMutableFileNode, IDirectoryNode
+from allmydata.scripts.common import (
+    write_introducer,
+)
 from foolscap.api import flushEventualQueue
 import allmydata.test.common_util as testutil
 from .common import (
@@ -66,7 +69,6 @@ from .common import (
     UseTestPlugins,
     MemoryIntroducerClient,
     get_published_announcements,
-    write_introducer,
 )
 from .matchers import (
     MatchesSameElements,
diff --git a/src/allmydata/test/test_introducer.py b/src/allmydata/test/test_introducer.py
index 4ccabd4e4..f6497eeb4 100644
--- a/src/allmydata/test/test_introducer.py
+++ b/src/allmydata/test/test_introducer.py
@@ -39,9 +39,11 @@ from allmydata.util import pollmixin, idlib, fileutil, yamlutil
 from allmydata.util.iputil import (
     listenOnUnused,
 )
+from allmydata.scripts.common import (
+    write_introducer,
+)
 import allmydata.test.common_util as testutil
 from .common import (
-    write_introducer,
     SyncTestCase,
     AsyncTestCase,
     AsyncBrokenTestCase,
diff --git a/src/allmydata/test/test_system.py b/src/allmydata/test/test_system.py
index 14bcb9c47..5a34dcc4d 100644
--- a/src/allmydata/test/test_system.py
+++ b/src/allmydata/test/test_system.py
@@ -47,7 +47,7 @@ from .web.common import (
 from allmydata.test.test_runner import RunBinTahoeMixin
 from . import common_util as testutil
 from .common_util import run_cli
-from .common import (
+from ..scripts.common import (
     write_introducer,
 )