add code sample for pandas-dev#38607

Author: simonjayhawkins

bisect/38607.py

@@ -0,0 +1,10 @@
+import pandas as pd
+
+print(pd.__version__)
+
+idx = pd.Index(["あ", b"a"], dtype="object")
+
+res = idx.astype(str)
+print(res)
+
+assert res[1] == "a"