Update _episodes/04-data-types-and-format.md

Author: orchid00

_episodes/04-data-types-and-format.md

@@ -17,7 +17,7 @@ objectives:
 keypoints:
     - Python uses two main data types text and numeric, these have a different names in basic Python and Pandas
     - Each column in a DataFrame has a shared data type for all rows
-    - Any data type can be converted to another type
+    - "The type of one column in a DataFrame can be checked using `dataFrameName[column_name].dtype`"
     - "Make conscious decisions about how to manage missing data"
     - "A DataFrame can be saved to a CSV file using `pd.read_csv`"
 ---