1 files changed, 9 insertions, 9 deletions
diff --git a/setuptools/dist.py b/setuptools/dist.py
index 8e34f35d..b1ebeb47 100644
--- a/setuptools/dist.py
+++ b/setuptools/dist.py
@@ -28,15 +28,15 @@ _Distribution = _get_unpatched(_Distribution)
 
 sequence = tuple, list
 
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+def check_importable(dist, attr, value):
+    try:
+        ep = pkg_resources.EntryPoint.parse('x='+value)
+        assert not ep.extras
+    except (TypeError,ValueError,AttributeError,AssertionError):
+        raise DistutilsSetupError(
+            "%r must be importable 'module:attrs' string (got %r)"
+            % (attr,value)
+        )
 
 
 def assert_string_list(dist, attr, value):