`Entry.contributors` returns `PersonAssociations` instead of `Person`

[mmaelicke]

I just found out that, Entry.contributors stills returns PersonAssociations instead of Person objects:

Originally posted by @AlexDo1 in https://github.com/VForWaTer/metacatalog/issues/248#issuecomment-1410333968

[mmaelicke]

Should be solvable similar to the solution in #244, which fixed #236

[mmaelicke]

@AlexDo1 I would close this without implementing it, as this is actually not a bug. The PersonAssociation further relates the PersonRoles. If we directly load the Person, we loose the information on the role with which the person is related to the Entry.

However, accessing the persons is trivial:

[pa.person for pa in entry.contributors]

returns a list Persons. A drawback is, that the PersonAssociation.to_dict method always includes the Entry. We could change that to only inlcude the Entry if deep=True. Then this code would produce better output:

[pa.to_dict() for pa in entry.contributors]

[{
  "person": `Person`,
  "role": `PersonRole`,
  "order": `Number`
}]

[AlexDo1]

Yes that's good.

The fact Persons are still easily accessible through PersonAssociation.person solves the issue for me.

The changes to PersonAssociation.to_dict to only include the Entry with deep=True would still be nice..