no issue
- returning and remembering the data, which was imported, is...
- not required when using the API
- not required when importing via script
- required for tests
- added an option to have control over it
- make more usage of local variables
- the GC cannot tidy up variables, which are defined outside of a loop, but used in the loop
- try to keep less memory in process
- reduce the number of properties we have to remember