diff --git a/README.md b/README.md
index 4dcaf68..ad6ab86 100644
--- a/README.md
+++ b/README.md
@@ -4,3 +4,7 @@ Providing FFI files for https://github.com/purescript/purescript-strings
 Available mirrors:
 
 https://github.com/purescript-python/purescript-python-ffi-index
+
+## Note on Regex
+
+`Data.String.Regex` and related modules is not supported yet, please check [#3](https://github.com/purescript-python/purescript-strings.py/issues/3) for details.
diff --git a/python-ffi/Data/String/CodeUnits.py b/python-ffi/Data/String/CodeUnits.py
index 328c749..fd93825 100644
--- a/python-ffi/Data/String/CodeUnits.py
+++ b/python-ffi/Data/String/CodeUnits.py
@@ -63,6 +63,10 @@ def _indexOfStartingAtImpl(just, nothing, x, startAt, s):
     i = s.find(x, startAt)
     return nothing if i == -1 else just(i)
 
+def _indexOfStartingAt(just):
+    return lambda nothing: lambda x: lambda startAt: lambda s: _indexOfStartingAtImpl(
+    just, nothing, x, startAt, s
+)
 
 globals()[
     "_indexOf'"