Most people treat packages just like bigger-than-classes chunks of related functionality and state. Typically there is a 'common' package for supporting stuff t

Most people treat packages just like bigger-than-classes chunks of related functionality and state. Typically there is a 'common' package for supporting stuff that is used all over the place, but these are not the data types most important for the project, these are just that project's particular incarnation of datetime utilities. The 'basic' package is certainly not common practice.