DOC: Standard function usage in 'pandas.DataFrame.map' method

[DarthKitten2130]

Pandas version checks

• I have checked that the issue still exists on the latest versions of the docs on main here

Location of the documentation

https://pandas.pydata.org/docs/dev/reference/api/pandas.DataFrame.map.html

Documentation problem

In the documentation for the 'map' method, there is no example of using the method with a standard function, only examples using lambda functions. These examples are available on other tutorial websites, but not in the primary documentation.

Suggested fix for documentation

I have created a PR for this issue which shows an example of a basic function and how it can be implemented with the DataFrame already outlined in the documentation.