diff --git a/isort/isort.py b/isort/isort.py
index <HASH>..<HASH> 100644
--- a/isort/isort.py
+++ b/isort/isort.py
@@ -220,7 +220,7 @@ class _SortImports:
             module_name = str(module_name)
 
         if sub_imports and config["order_by_type"]:
-            if module_name.isupper() and len(module_name) > 1:
+            if module_name.isupper() and len(module_name) > 1:  # see issue #376
                 prefix = "A"
             elif module_name[0:1].isupper():
                 prefix = "B"
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