update doctest

Author: jorisvandenbossche

pandas/core/generic.py

@@ -6809,12 +6809,12 @@ def convert_dtypes(
         2  3  z   <NA>  <NA>    20  200.0
 
         >>> dfn.dtypes
-        a             Int32
-        b    string[python]
-        c           boolean
-        d    string[python]
-        e             Int64
-        f           Float64
+        a      Int32
+        b     string
+        c    boolean
+        d     string
+        e      Int64
+        f    Float64
         dtype: object
 
         Start with a Series of strings and missing data represented by ``np.nan``.