Returns or sets the data on a particular component inside the user data map.
The user data is represented as a string for the sake of scripting languages, but from C++ it is
also possible to encode binary data.
This is equivalent to retrieving a UserDataItem with
UserDataMap.GetItem2 and then using the UserDataItem.Value
property.
Note: This is the Python-compliant version of the UserDataMap.ItemValue.
Since Python does not support input parameters on properties, UserDataMap.ItemValue will fail in Python.
