DOC: df.astype example using dictionary (pandas-dev#26990)

Author: stevennic

pandas/core/generic.py

@@ -5640,7 +5640,7 @@ def astype(self, dtype, copy=True, errors='raise', **kwargs):
 
         Cast col1 to int32 using a dictionary:
 
-         >>> df.astype({'col1': 'int32'}).dtypes
+        >>> df.astype({'col1': 'int32'}).dtypes
         col1    int32
         col2    int64
         dtype: object